Difference between revisions of "PulseAudio"

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(Failed to create sink input: sink is suspended)
(Readability fixes)
Line 32: Line 32:
  
 
PulseAudio can be stopped with:
 
PulseAudio can be stopped with:
  $ pulseaudio --kill
+
  $ pulseaudio -k
  
 
==Equalizer==
 
==Equalizer==
Line 97: Line 97:
 
====ossp====
 
====ossp====
 
Start {{Pkg|ossp}} with:
 
Start {{Pkg|ossp}} with:
  rc.d start osspd
+
  # /etc/rc.d/osspd start
 
+
Afterwards, add it to DAEMONS in {{ic|rc.conf}}.
+
  
 
====padsp wrapper (part of PulseAudio)====
 
====padsp wrapper (part of PulseAudio)====
Line 121: Line 119:
 
===GStreamer===
 
===GStreamer===
 
To make [[GStreamer]] use PulseAudio, you need to install {{Pkg|gstreamer0.10-good-plugins}}, execute {{ic|gstreamer-properties}} (part of ''gnome-media'' package) and select ''PulseAudio Sound Server'' in both Audio Input and Output. Alternatively, this can be done by setting the gconf variables {{ic|/system/gstreamer/0.10/default/audiosink}} to ''pulsesink'' and {{ic|/system/gstreamer/0.10/default/audiosrc}} to ''pulsesrc'':
 
To make [[GStreamer]] use PulseAudio, you need to install {{Pkg|gstreamer0.10-good-plugins}}, execute {{ic|gstreamer-properties}} (part of ''gnome-media'' package) and select ''PulseAudio Sound Server'' in both Audio Input and Output. Alternatively, this can be done by setting the gconf variables {{ic|/system/gstreamer/0.10/default/audiosink}} to ''pulsesink'' and {{ic|/system/gstreamer/0.10/default/audiosrc}} to ''pulsesrc'':
  $ gconftool-2 -t string --set /system/gstreamer/0.10/default/audiosink pulsesink
+
$ gconftool-2 -t string --set /system/gstreamer/0.10/default/audiosink pulsesink
  $ gconftool-2 -t string --set /system/gstreamer/0.10/default/audiosrc pulsesrc
+
$ gconftool-2 -t string --set /system/gstreamer/0.10/default/audiosrc pulsesrc
  
 
Some applications (like Rhythmbox) ignore the ''audiosink'' property, but rely instead on ''musicaudiosink'', which cannot be configured using {{ic|gstreamer-properties}} but needs to be manually set using {{ic|gconf-editor}} or the {{ic|gconftool-2}}:
 
Some applications (like Rhythmbox) ignore the ''audiosink'' property, but rely instead on ''musicaudiosink'', which cannot be configured using {{ic|gstreamer-properties}} but needs to be manually set using {{ic|gconf-editor}} or the {{ic|gconftool-2}}:
  $ gconftool-2 -t string --set /system/gstreamer/0.10/default/musicaudiosink pulsesink
+
$ gconftool-2 -t string --set /system/gstreamer/0.10/default/musicaudiosink pulsesink
  
 
===OpenAL===
 
===OpenAL===
Line 133: Line 131:
 
Edit the libao configuration file:
 
Edit the libao configuration file:
 
{{hc|/etc/libao.conf|2=default_driver=pulse}}
 
{{hc|/etc/libao.conf|2=default_driver=pulse}}
Be sure to remove the ''dev=default'' option of the alsa driver or adjust it to specify a specific Pulse sink name or number. Alternatively, note that you could keep the libao standard of outputting to the ''alsa'' driver and its default device if you install {{Pkg|pulseaudio-alsa}} since the ALSA default device then '''is''' PulseAudio.
+
Be sure to remove the {{ic|1=dev=default}} option of the alsa driver or adjust it to specify a specific Pulse sink name or number. Alternatively, note that you could keep the libao standard of outputting to the ''alsa'' driver and its default device if you install {{Pkg|pulseaudio-alsa}} since the ALSA default device then '''is''' PulseAudio.
 
   
 
   
 
===ESD===
 
===ESD===
Line 151: Line 149:
 
  $ start-pulseaudio-x11
 
  $ start-pulseaudio-x11
  
If you are not running Gnome, KDE or XFCE and your {{ic|~/.xinitrc}} does not source the scripts in {{ic|/etc/X11/xinit/xinitrc.d}} (such as is done in the example file {{ic|/etc/skel/.xinitrc}}) then you can launch PulseAudio on boot by adding the following line to ~/.xinitrc:
+
If you are not running Gnome, KDE or XFCE and your {{ic|~/.xinitrc}} does not source the scripts in {{ic|/etc/X11/xinit/xinitrc.d}} (such as is done in the example file {{ic|/etc/skel/.xinitrc}}) then you can launch PulseAudio on boot with:
/usr/bin/start-pulseaudio-x11
+
{{hc|~/.xinitrc|
 +
/usr/bin/start-pulseaudio-x11
 +
}}
  
 
===GNOME===
 
===GNOME===
Line 160: Line 160:
 
PulseAudio is ''not'' a drop-in replacement for aRts. Users of KDE 3 cannot use PulseAudio. However note, recent versions of PulseAudio may have eliminated the prohibition:
 
PulseAudio is ''not'' a drop-in replacement for aRts. Users of KDE 3 cannot use PulseAudio. However note, recent versions of PulseAudio may have eliminated the prohibition:
  
See: http://www.pulseaudio.org/wiki/PerfectSetup KDE 3 uses the artsd sound server by default. However, artsd itself can be configured to use an Esound backend. Edit kcmartsrc (either in /etc/kde or /usr/share/config for global configuration or .kde/share/config to configure only one user) like this:
+
See: http://www.pulseaudio.org/wiki/PerfectSetup KDE 3 uses the artsd sound server by default. However, artsd itself can be configured to use an Esound backend. Edit {{ic|kcmartsrc}} (either in {{ic|/etc/kde}} or {{ic|/usr/share/config}} for global configuration or {{ic|.kde/share/config}} to configure only one user) like this:
  
 
  [Arts]
 
  [Arts]
Line 202: Line 202:
  
 
====Muted audio device====
 
====Muted audio device====
If one experiences no audio output via any means while using ALSA, attempt to unmute the sound card.  To do this, launch alsamixer and make sure each column has a green 00 under it (this can be toggled by pressing 'm')
+
If one experiences no audio output via any means while using ALSA, attempt to unmute the sound card.  To do this, launch {{ic|alsamixer}} and make sure each column has a green 00 under it (this can be toggled by pressing {{keypress|m}}):
 
  $ alsamixer -c 0
 
  $ alsamixer -c 0
  
Line 222: Line 222:
  
 
====The only device shown is "dummy output"====
 
====The only device shown is "dummy output"====
This may be caused by different reasons, one of them being the .asoundrc file in $HOME is taking precedence over the systemwide /etc/asound.conf.
+
This may be caused by different reasons, one of them being the {{ic|.asoundrc}} file in $HOME is taking precedence over the systemwide {{ic|/etc/asound.conf}}.
  
The user file is modified also by the tool '''asoundconf''' or by its graphical variant '''asoundconf-gtk''' (the latter is named "Default sound card" in the menu) as soon as it  runs.  Prevent the effects of .asoundrc altogether by commenting the last line like this:
+
The user file is modified also by the tool {{ic|asoundconf}} or by its graphical variant {{ic|asoundconf-gtk}} (the latter is named "Default sound card" in the menu) as soon as it  runs.  Prevent the effects of {{ic|.asoundrc}} altogether by commenting the last line like this:
 +
{{hc|.asoundrc|
 +
# </home/<yourusername>/.asoundrc.asoundconf>
 +
}}
  
#</home/<yourusername>/.asoundrc.asoundconf>
+
Maybe some program is monopolizing the audio device:
 +
{{hc|# fuser -v /dev/snd/*|
 +
                    USER      PID  ACCESS COMMAND
 +
/dev/snd/controlC0:  root        931 F....  timidity
 +
                    bob        1195 F....  panel-6-mixer
 +
/dev/snd/controlC1:  bob        1195 F....  panel-6-mixer
 +
                    bob        1215 F....  pulseaudio
 +
/dev/snd/pcmC0D0p:  root        931 F...m  timidity
 +
/dev/snd/seq:        root        931 F....  timidity
 +
/dev/snd/timer:      root        931 f....  timidity
 +
}}
  
 
Maybe some program is monopolizing the audio device. Try this command:
 
# fuser -v /dev/snd/*
 
 
If the output looks like this:
 
                      USER      PID  ACCESS COMMAND
 
/dev/snd/controlC0:  root        931 F....  timidity
 
                      bob        1195 F....  panel-6-mixer
 
/dev/snd/controlC1:  bob        1195 F....  panel-6-mixer
 
                      bob        1215 F....  pulseaudio
 
/dev/snd/pcmC0D0p:  root        931 F...m  timidity
 
/dev/snd/seq:        root        931 F....  timidity
 
/dev/snd/timer:      root        931 f....  timidity
 
 
That means timidity blocks pulseaudio from accessing the audio devices. Just killing timidity will make the sound work again.
 
That means timidity blocks pulseaudio from accessing the audio devices. Just killing timidity will make the sound work again.
 
[to be improved and completed]
 
 
  
 
Another reason is [[FluidSynth]] conclicting with pulseaudio as discussed in [https://bbs.archlinux.org/viewtopic.php?id=154002 this thread]. The solution is to remove FluidSynth:
 
Another reason is [[FluidSynth]] conclicting with pulseaudio as discussed in [https://bbs.archlinux.org/viewtopic.php?id=154002 this thread]. The solution is to remove FluidSynth:
Line 261: Line 258:
 
Some user [https://bbs.archlinux.org/viewtopic.php?id=117420 report] huge delays or even no sound when the bluetooth connection does not send any data. This is due to an idle-suspend-module that puts the related sinks/sources automatically into suspend. As this can cause problems with headset, the responsible module can be deactivated.  
 
Some user [https://bbs.archlinux.org/viewtopic.php?id=117420 report] huge delays or even no sound when the bluetooth connection does not send any data. This is due to an idle-suspend-module that puts the related sinks/sources automatically into suspend. As this can cause problems with headset, the responsible module can be deactivated.  
  
  1. cp /etc/pulse/default.pa ~/.pulse/default.pa
+
  $ cp /etc/pulse/default.pa ~/.pulse/default.pa
2. comment out the "load-module module-suspend-on-idle" line in ~/.pulse/default.pa
+
 
  3. pulseaudio -k && pulseaudio --start
+
{{hc|~/.pulse/default.pa|
 +
; load-module module-suspend-on-idle
 +
}}
 +
 
 +
  $ pulseaudio -k && pulseaudio --start
  
 
[http://robert.orzanna.de/2011/08/prevent-idle-suspend-with-bluetooth.html More information]
 
[http://robert.orzanna.de/2011/08/prevent-idle-suspend-with-bluetooth.html More information]
  
 
===Automatically switch to Bluetooth or USB headset===
 
===Automatically switch to Bluetooth or USB headset===
Add the following to your /etc/pulse/default.pa:
+
Add the following:
 
+
{{hc|/etc/pulse/default.pa|
# automatically switch to newly-connected devices
+
# automatically switch to newly-connected devices
load-module module-switch-on-connect
+
load-module module-switch-on-connect
 +
}}
  
 
===Pulse overwrites ALSA settings===
 
===Pulse overwrites ALSA settings===
Pulseaudio usually overwrites the ALSA settings- for example set with alsamixer- at start up, even when the alsa daemon is loaded. Since there seems to be no other way to restrict this behaviour, a workaround is to restore the alsa settings again after pulseaudio had started. Add the following command to {{ic|.xinitrc}} {{ic|.bash_login}} or any other autostart file:
+
Pulseaudio usually overwrites the ALSA settings- for example set with alsamixer- at start up, even when the alsa daemon is loaded. Since there seems to be no other way to restrict this behaviour, a workaround is to restore the alsa settings again after pulseaudio had started. Add the following command to {{ic|.xinitrc}} or {{ic|.bash_login}} or any other autostart file:
  
 
  restore_alsa() {
 
  restore_alsa() {
Line 292: Line 294:
 
Try resetting PulseAudio:
 
Try resetting PulseAudio:
 
  $ rm -rf /tmp/pulse* ~/.pulse*
 
  $ rm -rf /tmp/pulse* ~/.pulse*
  $ pulseaudio --kill
+
  $ pulseaudio -k
 
  $ pulseaudio --start
 
  $ pulseaudio --start
  
Line 299: Line 301:
 
===padevchooser===
 
===padevchooser===
 
If one cannot launch the PulseAudio Device Chooser, first (re)start the Avahi daemon as follows:
 
If one cannot launch the PulseAudio Device Chooser, first (re)start the Avahi daemon as follows:
  $ rc.d restart avahi-daemon
+
  # systemctl restart avahi-daemon
  
 
===Glitches, skips or crackling===
 
===Glitches, skips or crackling===
Line 306: Line 308:
 
Timer-based scheduling may expose issues in some ALSA drivers. On the other hand, other drivers might be glitchy without it on, so check to see what works on your system.  
 
Timer-based scheduling may expose issues in some ALSA drivers. On the other hand, other drivers might be glitchy without it on, so check to see what works on your system.  
  
To turn timer-based scheduling off, replace the line:
+
To turn timer-based scheduling off add {{ic|1=tsched=0}} in {{ic|/etc/pulse/default.pa}}:
load-module module-udev-detect
+
{{hc|/etc/pulse/default.pa|<nowiki>
in {{ic|/etc/pulse/default.pa}} by:
+
load-module module-udev-detect tsched=0
load-module module-udev-detect tsched=0
+
</nowiki>}}
Then restart the PulseAudio server.
+
 
 +
Then restart the PulseAudio server:
 +
$ pulseaudio -k
 +
$ pulseaudio --start
  
 
Do the reverse to enable timer-based scheduling, if not already enabled by default.
 
Do the reverse to enable timer-based scheduling, if not already enabled by default.
Line 318: Line 323:
 
===Setting the default fragment number and buffer size in Pulseaudio===
 
===Setting the default fragment number and buffer size in Pulseaudio===
 
   
 
   
1. Finding out your audio device parameters
+
====Finding out your audio device parameters (1/4)====
  
Run the following Bash commands to find your sound card buffering settings:
+
To find your sound card buffering settings:
  echo autospawn = no >> ~/.pulse/client.conf
+
  $ echo autospawn = no >> ~/.pulse/client.conf
  killall pulseaudio
+
  $ pulseaudio -k
  LANG=C timeout --foreground -k 10 -s kill 10 pulseaudio -vvvv 2>&1 | grep device.buffering -B 10
+
  $ LANG=C timeout --foreground -k 10 -s kill 10 pulseaudio -vvvv 2>&1 | grep device.buffering -B 10
  sed -i '$d' ~/.pulse/client.conf
+
  $ sed -i '$d' ~/.pulse/client.conf
  
 
For each sound card detected by Pulseaudio, you will see output similar to this:
 
For each sound card detected by Pulseaudio, you will see output similar to this:
Line 342: Line 347:
 
Take note the buffer_size and fragment_size values for the relevant sound card.
 
Take note the buffer_size and fragment_size values for the relevant sound card.
  
2. Calculate your fragment size in msecs and number of fragments
+
====Calculate your fragment size in msecs and number of fragments (2/4)====
  
Pulseaudio's default sampling rate and bit depth are set to 44100Hz @ 16 bits.
+
Pulseaudio's default sampling rate and bit depth are set to {{ic|44100Hz}} @ {{ic|16 bits}}.
  
With this configuration, the bit rate we need is 44100*16 = 705600 bits per second. That's 1411200 bps for stereo.
+
With this configuration, the bit rate we need is {{ic|44100}}*{{ic|16}} = {{ic|705600 bits per second. That's {{ic|1411200 bps}} for stereo.
  
 
Let's take a look at the parameters we've found in the previous step:
 
Let's take a look at the parameters we've found in the previous step:
Line 353: Line 358:
 
  device.buffering.fragment_size = "384000" => 384000/1411200 = 0.272108843537s = 272 msecs
 
  device.buffering.fragment_size = "384000" => 384000/1411200 = 0.272108843537s = 272 msecs
  
3.Modify Pulseaudio's configuration file
+
====Modify Pulseaudio's configuration file (3/4)====
 
+
Edit the configuration file located at {{ic|/etc/pulse/daemon.conf}} using the editor of your choice.
+
 
+
For example:
+
sudo vi /etc/pulse/daemon.conf
+
 
+
Locate & uncomment (remove leading semicolons) these lines:
+
 
+
; default-fragments = X
+
; default-fragment-size-msec = Y
+
  
 +
{{hc|/etc/pulse/daemon.conf|<nowiki>
 +
; default-fragments = X
 +
; default-fragment-size-msec = Y
 +
</nowiki>}}
  
 
In the previous step, we calculated the fragment size parameter.
 
In the previous step, we calculated the fragment size parameter.
The number of fragments is simply buffer_size/fragment_size, which in this case (544/272) is 2.
+
The number of fragments is simply buffer_size/fragment_size, which in this case ({{ic|544/272}}) is {{ic|2}}:
  
Edit the lines to use your calculated settings:
+
{{hc|/etc/pulse/daemon.conf|<nowiki>
 +
; default-fragments = '''272'''
 +
; default-fragment-size-msec = '''2'''
 +
</nowiki>}}
  
default-fragment-size-msec = 272
+
====Restart the Pulseaudio daemon (4/4)====
default-fragments = 2
+
  
Save the file.
+
$ pulseaudio -k
 +
$ pulseaudio --start
  
 
+
For more information, see: [http://forums.linuxmint.com/viewtopic.php?f=42&t=44862 Linux Mint topic]
4.Restart the Pulseaudio daemon
+
 
+
pulseaudio -k
+
pulseaudio --start
+
 
+
Source: [http://forums.linuxmint.com/viewtopic.php?f=42&t=44862 kwevej @ Linux Mint Forums]
+
  
 
===Laggy sound===
 
===Laggy sound===
 
This issue is due to incorrect buffer sizes.
 
This issue is due to incorrect buffer sizes.
Edit {{ic|/etc/pulse/daemon.conf}}
 
  
Either disable any modifications (if any) to these entries, or, if issue still exists, uncomment and change them in the following way:
+
Either disable any modifications (if any) to these entries, or, if issue still exists, uncomment:
default-fragments = 8
+
{{hc|/etc/pulse/daemon.conf|<nowiki>
default-fragment-size-msec = 5
+
default-fragments = 8
 +
default-fragment-size-msec = 5
 +
</nowiki>}}
  
 
===Choppy, overdriven sound===
 
===Choppy, overdriven sound===
Choppy sound in pulsaudio can result from wrong settings for the sample rate in {{Ic|/etc/pulse/daemon.conf}}. Try changing the line
+
Choppy sound in pulsaudio can result from wrong settings for the sample rate. Try:
; default-sample-rate = 44100
+
{{hc|/etc/pulse/daemon.conf|<nowiki>
to
+
default-sample-rate = 48000
default-sample-rate = 48000
+
</nowiki>}}
 
and restart the PulseAudio server.
 
and restart the PulseAudio server.
  
If one experiences choppy sound in applications using openAL, change the sample rate in /etc/openal/alsoft.conf:
+
If one experiences choppy sound in applications using openAL, change the sample rate in {{ic|/etc/openal/alsoft.conf}}:
 
  frequency = 48000
 
  frequency = 48000
  
Line 413: Line 410:
 
Per default, it seems as if changing the volume in an application sets the global system volume to that level instead of only affecting the respective application. Applications setting their volume on startup will therefore cause the system volume to "jump".
 
Per default, it seems as if changing the volume in an application sets the global system volume to that level instead of only affecting the respective application. Applications setting their volume on startup will therefore cause the system volume to "jump".
  
Fix this by uncommenting the line
+
Fix this by:
flat-volumes = yes
+
{{hc|/etc/pulse/daemon.conf|<nowiki>
and changing it to:
+
flat-volumes = no
flat-volumes = no
+
</nowiki>}}
in
+
/etc/pulse/daemon.conf
+
 
and then restarting PulseAudio by executing
 
and then restarting PulseAudio by executing
  pulseaudio --kill && pulseaudio --start
+
  $ pulseaudio -k && pulseaudio --start
  
 
When Pulse comes back after a few seconds, applications will not alter the global system volume anymore but have their own volume level again.
 
When Pulse comes back after a few seconds, applications will not alter the global system volume anymore but have their own volume level again.
  
{{Note|A previously installed and removed pulseaudio-equalizer may leave behind remnants of the setup in {{Ic|$HOME/.pulse/default.pa}} which can also cause maximized volume trouble. Comment that out as needed.}}
+
{{Note|A previously installed and removed pulseaudio-equalizer may leave behind remnants of the setup in {{Ic|~/.pulse/default.pa}} which can also cause maximized volume trouble. Comment that out as needed.}}
  
 
===No mic on ThinkPad T400/T500/T420===
 
===No mic on ThinkPad T400/T500/T420===
Run
+
Run:
 
  alsamixer -c 0
 
  alsamixer -c 0
 
Maximize the volume of/unmute the "Internal Mic".
 
Maximize the volume of/unmute the "Internal Mic".
  
Once you see the device with
+
Once you see the device with:
 
  arecord -l
 
  arecord -l
 
you might still need to adjust the settings. The microphone and the audio jack are duplexed. Set the configuration of the internal audio in pavucontrol to ''Analog Stereo Duplex''.
 
you might still need to adjust the settings. The microphone and the audio jack are duplexed. Set the configuration of the internal audio in pavucontrol to ''Analog Stereo Duplex''.
Line 440: Line 435:
  
 
===Sound output is only mono on M-Audio Audiophile 2496 sound card===
 
===Sound output is only mono on M-Audio Audiophile 2496 sound card===
Add the following to /etc/pulseaudio/default.pa:
+
Add the following:
load-module module-alsa-sink sink_name=delta_out device=hw:M2496 format=s24le channels=10 channel_map=left,right,aux0,aux1,aux2,aux3,aux4,aux5,aux6,aux7
+
{{hc|/etc/pulseaudio/default.pa|<nowiki>
load-module module-alsa-source source_name=delta_in device=hw:M2496 format=s24le channels=12 channel_map=left,right,aux0,aux1,aux2,aux3,aux4,aux5,aux6,aux7,aux8,aux9
+
load-module module-alsa-sink sink_name=delta_out device=hw:M2496 format=s24le channels=10 channel_map=left,right,aux0,aux1,aux2,aux3,aux4,aux5,aux6,aux7
set-default-sink delta_out
+
load-module module-alsa-source source_name=delta_in device=hw:M2496 format=s24le channels=12 channel_map=left,right,aux0,aux1,aux2,aux3,aux4,aux5,aux6,aux7,aux8,aux9
set-default-source delta_in
+
set-default-sink delta_out
 +
set-default-source delta_in
 +
</nowiki>}}
  
 
===Static Noise in Microphone Recording===
 
===Static Noise in Microphone Recording===
If we are getting static noise in skype, gnome-sound-recorder, arecord, etc.'s recordings then the sound card samplerate is incorrect. That is why there is static noise in linux microphone recordings. To fix this We need to set sample-rate in /etc/pulse/daemon.conf for the sound hardware.
+
If we are getting static noise in skype, gnome-sound-recorder, arecord, etc.'s recordings then the sound card samplerate is incorrect. That is why there is static noise in linux microphone recordings. To fix this We need to set sample-rate in {{ic|/etc/pulse/daemon.conf}} for the sound hardware.
  
====1. Determine soundcards in the system====
+
====Determine soundcards in the system (1/5)====
 
This requires alsa-utils and related packages to be installed:
 
This requires alsa-utils and related packages to be installed:
$  arecord --list-devices
+
{{hc|$  arecord --list-devices|
 +
**** List of CAPTURE Hardware Devices ****
 +
card 0: Intel [HDA Intel], device 0: ALC888 Analog [ALC888 Analog]
 +
  Subdevices: 1/1
 +
  Subdevice #0: subdevice #0
 +
card 0: Intel [HDA Intel], device 2: ALC888 Analog [ALC888 Analog]
 +
  Subdevices: 1/1
 +
  Subdevice #0: subdevice #0
 +
}}
  
output:
+
Sound card is {{ic|hw:0,0}}.
    **** List of CAPTURE Hardware Devices ****
+
    card 0: Intel [HDA Intel], device 0: ALC888 Analog [ALC888 Analog]
+
      Subdevices: 1/1
+
      Subdevice #0: subdevice #0
+
    card 0: Intel [HDA Intel], device 2: ALC888 Analog [ALC888 Analog]
+
      Subdevices: 1/1
+
      Subdevice #0: subdevice #0
+
  
soundcard is hw:0,0
+
====Determine sampling-rate of the sound card (2/5)====
 +
{{hc|arecord -f dat -r 60000 -D hw:0,0 -d 5 test.wav|
 +
"Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 60000 Hz, Stereo
 +
Warning: rate is not accurate (requested = 60000Hz, '''got = 96000Hz''')
 +
please, try the plug plugin
 +
}}
  
====2. Determine sampling-rate of the sound card====
+
observe, the {{ic|got = 96000Hz}}. This is the max sample-rate of our card.
arecord -f dat -r 60000 -D hw:0,0 -d 5 test.wav
+
  
output:
+
====Setting the soundcard's sampling rate into pulse audio configuration (3/5)====
  "Recording WAVE 'test.wav' : Signed 16 bit Little Endian, Rate 60000 Hz, Stereo
+
The default sample-rate in pulseaudio:
  Warning: rate is not accurate (requested = 60000Hz, '''got = 96000Hz''')
+
{{hc|$ grep "default-sample-rate" /etc/pulse/daemon.conf|
  please, try the plug plugin
+
; default-sample-rate = 44100
 +
}}
  
observe, the '''got = 96000Hz''', this is the max sample-rate of our card.
+
{ic|44100}} is disabled and needs to be changed to {{ic|96000}}:
 +
# sed 's/; default-sample-rate = 44100/default-sample-rate = 96000/g' -i /etc/pulse/daemon.conf
  
====3. Setting the soundcard's sampling rate into pulse audio configuration====
+
====Restart pulseaudio to apply the new settings (4/5)====
the default sample-rate in pulseaudio is
+
  $ pulseaudio -k
grep "sample-rate" /etc/pulse/daemon.conf
+
  $ pulseaudio --start
 
+
output:
+
    ; default-sample-rate = 44100
+
 
+
It is 44100 and is disabled. Let us set our sound card's settings into pulseaudio configuation file
+
su -c "sed 's/; default-sample-rate = 44100/default-sample-rate = 96000/g' -i /etc/pulse/daemon.conf"
+
 
+
Let us verify the changes to deamon.conf
+
grep "sample-rate" /etc/pulse/daemon.conf
+
output:
+
  default-sample-rate = 96000
+
and it is done.
+
 
+
====4. Restart pulseaudio to apply the new settings====
+
  pulseaudio --kill
+
  pulseaudio --start
+
  
====5. Finally check by recording and playing it back====
+
====Finally check by recording and playing it back (5/5)====
 
Let us record some voice using mic for say 10 seconds. Make sure the mic is not muted and all
 
Let us record some voice using mic for say 10 seconds. Make sure the mic is not muted and all
  arecord -f cd -d 10 test-mic.wav
+
  $ arecord -f cd -d 10 test-mic.wav
  
 
After 10 seconds, let us play the recording...
 
After 10 seconds, let us play the recording...
  aplay test-mic.wav
+
  $ aplay test-mic.wav
  
 
Now hopefully, there is no static noise in microphone recording anymore.
 
Now hopefully, there is no static noise in microphone recording anymore.
Line 506: Line 494:
 
[[Bluetooth#My_device_is_paired_but_no_sound_is_played_from_it|See the article in Bluetooth section]]
 
[[Bluetooth#My_device_is_paired_but_no_sound_is_played_from_it|See the article in Bluetooth section]]
  
Starting from PulseAudio 2.99 and bluez 4.101 you should '''avoid''' using Socket interface. Do NOT add
+
Starting from PulseAudio 2.99 and bluez 4.101 you should '''avoid''' using Socket interface. Do NOT use:
[General]
+
{{hc|/etc/bluetooth/audio.conf|<nowiki>
Enable=Socket
+
[General]
to your /etc/bluetooth/audio.conf.
+
Enable=Socket
If you face problems with A2DP and PA 2.99 make sure you have SBC library:
+
</nowiki>}}
  pacman -S sbc  
+
If you face problems with A2DP and PA 2.99 make sure you have {{pkg|sbc}} library:
 +
  # pacman -S sbc  
  
 
=== Subwoofer stops working after end of every song  ===
 
=== Subwoofer stops working after end of every song  ===
Line 522: Line 511:
  
 
=== Pulseaudio uses wrong microphone ===
 
=== Pulseaudio uses wrong microphone ===
If Pulseaudio uses the wrong microphone, and changing the Input Device with Pavucontrol did not help, take a look at alsamixer. It seems that Pavucontrol does not always set the input source correctly.<br>
+
If Pulseaudio uses the wrong microphone, and changing the Input Device with Pavucontrol did not help, take a look at alsamixer. It seems that Pavucontrol does not always set the input source correctly.
Run:
+
  
 
  $ alsamixer
 
  $ alsamixer
  
press F6 and choose your sound card, e.g. HDA Intel. Now press F5 to display all items. Try to find the item: {{ic|Input Source}}. With the up/down arrow keys you are able to change the input source. <br>
+
Press {{keypress|F6}} and choose your sound card, e.g. HDA Intel. Now press {{keypress|F5}} to display all items. Try to find the item: {{ic|Input Source}}. With the up/down arrow keys you are able to change the input source.
 +
 
 
Now try if the correct microphone is used for recording.
 
Now try if the correct microphone is used for recording.
  
Line 540: Line 529:
 
Known issue (won't fix): https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/223133
 
Known issue (won't fix): https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/223133
  
If sound doesn't play when Pulseaudio's volume is set below a certain level, try editing {{ic|/etc/pulse/default.pa}} and changing:
+
If sound doesn't play when Pulseaudio's volume is set below a certain level, try {{ic|1=ignore_dB=1}} in {{ic|/etc/pulse/default.pa}}:
{{hc|/etc/pulse/default.pa|<nowiki>
+
load-module module-udev-detect
+
</nowiki>}}
+
to
+
 
{{hc|/etc/pulse/default.pa|<nowiki>
 
{{hc|/etc/pulse/default.pa|<nowiki>
 
load-module module-udev-detect ignore_dB=1
 
load-module module-udev-detect ignore_dB=1
Line 551: Line 536:
 
However, be aware that it may cause another bug preventing pulseaudio to unmute speakers when headphones or other audio devices are unplugged
 
However, be aware that it may cause another bug preventing pulseaudio to unmute speakers when headphones or other audio devices are unplugged
 
=== Low volume for internal mic ===
 
=== Low volume for internal mic ===
If you experience low volume on internal notebook microphone, try setting  
+
If you experience low volume on internal notebook microphone, try setting:
 
{{hc|/etc/pulse/default.pa|<nowiki>
 
{{hc|/etc/pulse/default.pa|<nowiki>
 
set-source-volume 1 300000
 
set-source-volume 1 300000
</nowiki>}} at the end of the file.
+
</nowiki>}}
  
 
==External links==
 
==External links==

Revision as of 13:32, 4 April 2013

PulseAudio is the default sound server that serves as a proxy to sound applications using existing kernel sound components like ALSA or OSS. Since ALSA is included in Arch Linux by default so the most common deployment scenarios include PulseAudio with ALSA.

Summary help replacing me
PulseAudio is a general purpose sound server. For a list of features, see Wikipedia:PulseAudio#Features.
Related Articles
PulseAudio/Examples

Contents

Installation

Running

Note: Pulseaudio requires D-Bus to function.
Note: Most X11 environments start pulseaudio automatically with the X11 session.

In the unlikely event that pulseaudio is not automatically called upon entering X, it can can be started with:

$ pulseaudio --start

PulseAudio can be stopped with:

$ pulseaudio -k

Equalizer

Newer pulseaudio versions have an intergrated 10-band equalizer system. In order to use the equalizer do the following:

Load equalizer sink module

$ pactl load-module module-equalizer-sink

Install and run the gui frontend

# pacman -S --needed python2-pyqt
$ qpaeq
Note: If qpaeq has no effect, install pavucontrol and change "ALSA Playback on" to "FFT based equalizer on ..." while the media player is running.

Load equalizer module on every boot

Edit the file /etc/pulse/default.pa with your favorite editor and append the following lines:

### Load the integrated pulseaudio equalizer module
load-module module-equalizer-sink

Backend Configuration

ALSA

Note: Optional PKGs are needed only if running x86_64 and wanting to have sound for 32 bit programs (like Wine).

For the applications that do not support PulseAudio and support ALSA it is recommended to install the PulseAudio plugin for ALSA. This package also contains the necessary /etc/asound.conf for configuring ALSA to use PulseAudio.

To prevent applications from using ALSA's OSS emulation and bypassing Pulseaudio (thereby preventing other applications from playing sound), make sure the module snd_pcm_oss is not being loaded at boot. If it is currently loaded (lsmod|grep oss), disable it by executing:

# rmmod snd_pcm_oss

ALSA/dmix without grabbing hardware device

Note: This section describes alternative configuration, which is generally NOT recommended.

You may want to use ALSA directly in most of your applications and to be able to use other applications, which constantly require PulseAudio at the same time. The following steps allow you to make PulseAudio use dmix instead of grabbing ALSA hardware device.

  • Remove package pulseaudio-alsa, which provides compatibility layer between ALSA applications and PulseAudio. After this your ALSA apps will use ALSA directly without being hooked by Pulse.
$ sudo pacman -R pulseaudio-alsa
  • Edit /etc/pulse/default.pa.
Find and uncomment lines which load backend drivers. Add device parameters as follows. Then find and comment lines which load autodetect modules.
load-module module-alsa-sink device=dmix
load-module module-alsa-source device=dsnoop
# load-module module-udev-detect
# load-module module-detect
  • Optional: If you use kdemultimedia-kmix you may want to control ALSA volume instead of PulseAudio volume:
$ echo export KMIX_PULSEAUDIO_DISABLE=1 > ~/.kde4/env/kmix_disable_pulse.sh
$ chmod +x ~/.kde4/env/kmix_disable_pulse.sh
  • Now, reboot your computer and try running alsa and pulseaudio applications at the same time. They both should produce sound simultaneously.
Use pavucontrol to control PulseAudio volume if needed.

OSS

There are multiple ways of making OSS-only programs play to PulseAudio:

ossp

Start ossp with:

# /etc/rc.d/osspd start

padsp wrapper (part of PulseAudio)

Programs using OSS can work with PulseAudio by starting it with padsp:

$ padsp OSSprogram

A few examples:

$ padsp aumix
$ padsp sox foo.wav -t ossdsp /dev/dsp

One can also rename the OSSprogram-bin binary and replace it with a script like this:

/usr/bin/OSSProgram
#!/bin/sh
if test -x /usr/bin/padsp; then
    exec /usr/bin/padsp /usr/bin/OSSprogram-bin "$@"
else
    exec /usr/bin/OSSprogram "$@"
fi

GStreamer

To make GStreamer use PulseAudio, you need to install gstreamer0.10-good-plugins, execute gstreamer-properties (part of gnome-media package) and select PulseAudio Sound Server in both Audio Input and Output. Alternatively, this can be done by setting the gconf variables /system/gstreamer/0.10/default/audiosink to pulsesink and /system/gstreamer/0.10/default/audiosrc to pulsesrc:

$ gconftool-2 -t string --set /system/gstreamer/0.10/default/audiosink pulsesink
$ gconftool-2 -t string --set /system/gstreamer/0.10/default/audiosrc pulsesrc

Some applications (like Rhythmbox) ignore the audiosink property, but rely instead on musicaudiosink, which cannot be configured using gstreamer-properties but needs to be manually set using gconf-editor or the gconftool-2:

$ gconftool-2 -t string --set /system/gstreamer/0.10/default/musicaudiosink pulsesink

OpenAL

OpenAL Soft should use PulseAudio by default, but can be explicitly configured to do so:
/etc/openal/alsoft.conf
drivers=pulse,alsa

libao

Edit the libao configuration file:

/etc/libao.conf
default_driver=pulse

Be sure to remove the dev=default option of the alsa driver or adjust it to specify a specific Pulse sink name or number. Alternatively, note that you could keep the libao standard of outputting to the alsa driver and its default device if you install pulseaudio-alsa since the ALSA default device then is PulseAudio.

ESD

PulseAudio is a drop-in replacement for the enlightened sound daemon (ESD). While PulseAudio is running, ESD clients should be able to output to it without configuration.

Desktop Environments

General X11

Note: As mentioned previously, PulseAudio is very likely launched automatically via either /etc/X11/xinit/xinitrc.d/pulseaudio or the files in /etc/xdg/autostart/ if users have some DE installed.

Check to see if PulseAudio is running:

$ ps aux | grep pulse
facade   1794  0.0  0.0 360464  6532 ?        S<l  15:33   0:00 /usr/bin/pulseaudio --start
facade   1827  0.0  0.0  68888  2608 ?        S    15:33   0:00 /usr/lib/pulse/gconf-helper

If Pulseaudio is not running and users are using X, the following will start PulseAudio with the needed the X11 plugins manually:

$ start-pulseaudio-x11

If you are not running Gnome, KDE or XFCE and your ~/.xinitrc does not source the scripts in /etc/X11/xinit/xinitrc.d (such as is done in the example file /etc/skel/.xinitrc) then you can launch PulseAudio on boot with:

~/.xinitrc
/usr/bin/start-pulseaudio-x11

GNOME

As of GNOME 3, GNOME fully integrates with PulseAudio and no extra configuration is needed.

KDE 3

PulseAudio is not a drop-in replacement for aRts. Users of KDE 3 cannot use PulseAudio. However note, recent versions of PulseAudio may have eliminated the prohibition:

See: http://www.pulseaudio.org/wiki/PerfectSetup KDE 3 uses the artsd sound server by default. However, artsd itself can be configured to use an Esound backend. Edit kcmartsrc (either in /etc/kde or /usr/share/config for global configuration or .kde/share/config to configure only one user) like this:

[Arts]
Arguments=\s-F 10 -S 4096 -a esd -n -s 1 -m artsmessage -c drkonqi -l 3 -f
NetworkTransparent=true
SuspendTime=1

KDE Plasma Workspaces and Qt4

PulseAudio, it will be used by KDE/Qt4 applications. For more information see the KDE page in the PulseAudio wiki.

PulseAudio support has been merged into KMix, the default KDE sound mixer.

If the phonon-gstreamer backend is used for Phonon, GStreamer should also be configured to use PulseAudio by installing gstreamer0.10-good-plugins.

One useful tidbit from that page is to add load-module module-device-manager to /etc/pulse/default.pa.

Additionally, the kdeplasma-applets-veromixAUR is available in the AUR as a KDE alternative to KMix or pavucontrol.

Xfce

Applications running under Xfce can take advantage of PulseAudio. To manage PulseAudio settings you can use pavucontrol.

Applications

Audacious

Audacious natively supports PulseAudio. In order to use it, set Audacious Preferences -> Audio -> Current output plugin to 'PulseAudio Output Plugin'.

Java/OpenJDK 6

Create a wrapper for the java executable using padsp as seen on the Java sound with Pulseaudio page.

Music Player Daemon (MPD)

configure MPD to use PulseAudio. See also MPD/Tips_and_Tricks#MPD_.26_PulseAudio.

MPlayer

MPlayer natively supports PulseAudio output with the "-ao pulse" option. It can also be configured to default to PulseAudio output, in ~/.mplayer/config for per-user, or /etc/mplayer/mplayer.conf for system-wide:

/etc/mplayer/mplayer.conf
ao=pulse

Skype (x86_64 only)

Install lib32-libpulse, otherwise the following error will occur when trying to initiate a call: "Problem with Audio Playback".

Troubleshooting

No sound after install

Muted audio device

If one experiences no audio output via any means while using ALSA, attempt to unmute the sound card. To do this, launch alsamixer and make sure each column has a green 00 under it (this can be toggled by pressing Template:Keypress):

$ alsamixer -c 0

Bad configuration files

If after starting pulseaudio, the system outputs no sound, it may be necessary to delete the contents of ~/.pulse. Pulseaudio will automatically create new configuration files on its next start.

Flash Content

Since Adobe Flash does not directly support PulseAudio the recommended way is to configure ALSA to use the virtual PulseAudio soundcard.

Alternatively you may try out libflashsupport-pulseAUR from the AUR.

Note: This may invariably crash the flash plugin.

No cards

If PulseAudio starts, run pacmd list. If no cards are reported, make sure that the ALSA devices are not in use:

$ fuser -v /dev/snd/*
$ fuser -v /dev/dsp

Make sure any applications using the pcm or dsp files are shut down before restarting PulseAudio.

The only device shown is "dummy output"

This may be caused by different reasons, one of them being the .asoundrc file in $HOME is taking precedence over the systemwide /etc/asound.conf.

The user file is modified also by the tool asoundconf or by its graphical variant asoundconf-gtk (the latter is named "Default sound card" in the menu) as soon as it runs. Prevent the effects of .asoundrc altogether by commenting the last line like this:

.asoundrc
# </home/<yourusername>/.asoundrc.asoundconf>

Maybe some program is monopolizing the audio device:

# fuser -v /dev/snd/*
                     USER       PID  ACCESS COMMAND
/dev/snd/controlC0:  root        931 F....  timidity
                     bob        1195 F....  panel-6-mixer
/dev/snd/controlC1:  bob        1195 F....  panel-6-mixer
                     bob        1215 F....  pulseaudio
/dev/snd/pcmC0D0p:   root        931 F...m  timidity
/dev/snd/seq:        root        931 F....  timidity
/dev/snd/timer:      root        931 f....  timidity

That means timidity blocks pulseaudio from accessing the audio devices. Just killing timidity will make the sound work again.

Another reason is FluidSynth conclicting with pulseaudio as discussed in this thread. The solution is to remove FluidSynth:

# pacman -Rnsc fluidsynth

KDE4

It may be that another output device set as preferred in phonon. Make sure that every setting reflects the preferred output device at the top, and check the playback streams tab in kmix to make sure that applications are using the device for output.

Failed to create sink input: sink is suspended

If you do not have any output sound and receive dozens of errors related to a suspended sink in your journalctl -b log, then backup first and then delete your user-specific pulse folders:

$ rm -r ~/.pulse ~/.pulse-cookie

Bluetooth headset replay problems

Some user report huge delays or even no sound when the bluetooth connection does not send any data. This is due to an idle-suspend-module that puts the related sinks/sources automatically into suspend. As this can cause problems with headset, the responsible module can be deactivated.

$ cp /etc/pulse/default.pa ~/.pulse/default.pa
~/.pulse/default.pa
; load-module module-suspend-on-idle
$ pulseaudio -k && pulseaudio --start

More information

Automatically switch to Bluetooth or USB headset

Add the following:

/etc/pulse/default.pa
# automatically switch to newly-connected devices
load-module module-switch-on-connect

Pulse overwrites ALSA settings

Pulseaudio usually overwrites the ALSA settings- for example set with alsamixer- at start up, even when the alsa daemon is loaded. Since there seems to be no other way to restrict this behaviour, a workaround is to restore the alsa settings again after pulseaudio had started. Add the following command to .xinitrc or .bash_login or any other autostart file:

restore_alsa() {
 while [ -z "`pidof pulseaudio`" ]; do
  sleep 0.5
 done
 alsactl -f /var/lib/alsa/asound.state restore 
}
restore_alsa &

Prevent Pulse from restarting after being killed

Sometimes you may wish to temporarily disable Pulse. In order to do so you will have to prevent Pulse from restarting after being killed.

$ echo autospawn=no > ~/.pulse/client.conf

Daemon startup failed

Try resetting PulseAudio:

$ rm -rf /tmp/pulse* ~/.pulse*
$ pulseaudio -k
$ pulseaudio --start

If there is no server running but pulseaudio fails to start with an error message "User-configured server at ... refusing to start/autospawn", the issue may be with PulseAudio settings from a previous login. Check to see if there are any stale properties attached to the X11 root window with pax11publish -d, and if there are, remove them with pax11publish -r before trying to start the server. This manual cleanup is always required when using LXDM because it does not restart the X server on logout; see LXDM#PulseAudio.

padevchooser

If one cannot launch the PulseAudio Device Chooser, first (re)start the Avahi daemon as follows:

# systemctl restart avahi-daemon

Glitches, skips or crackling

The newer implementation of PulseAudio sound server uses a timer-based audio scheduling instead of the traditional interrupt-driven approach.

Timer-based scheduling may expose issues in some ALSA drivers. On the other hand, other drivers might be glitchy without it on, so check to see what works on your system.

To turn timer-based scheduling off add tsched=0 in /etc/pulse/default.pa:

/etc/pulse/default.pa
load-module module-udev-detect tsched=0

Then restart the PulseAudio server:

$ pulseaudio -k
$ pulseaudio --start

Do the reverse to enable timer-based scheduling, if not already enabled by default.

Please report any such cards to PulseAudio Broken Sound Driver page

Setting the default fragment number and buffer size in Pulseaudio

Finding out your audio device parameters (1/4)

To find your sound card buffering settings:

$ echo autospawn = no >> ~/.pulse/client.conf
$ pulseaudio -k
$ LANG=C timeout --foreground -k 10 -s kill 10 pulseaudio -vvvv 2>&1 | grep device.buffering -B 10
$ sed -i '$d' ~/.pulse/client.conf

For each sound card detected by Pulseaudio, you will see output similar to this:

I: [pulseaudio] source.c:     alsa.long_card_name = "HDA Intel at 0xfa200000 irq 46"
I: [pulseaudio] source.c:     alsa.driver_name = "snd_hda_intel"
I: [pulseaudio] source.c:     device.bus_path = "pci-0000:00:1b.0"
I: [pulseaudio] source.c:     sysfs.path = "/devices/pci0000:00/0000:00:1b.0/sound/card0"
I: [pulseaudio] source.c:     device.bus = "pci"
I: [pulseaudio] source.c:     device.vendor.id = "8086"
I: [pulseaudio] source.c:     device.vendor.name = "Intel Corporation"
I: [pulseaudio] source.c:     device.product.name = "82801I (ICH9 Family) HD Audio Controller"
I: [pulseaudio] source.c:     device.form_factor = "internal"
I: [pulseaudio] source.c:     device.string = "front:0"
I: [pulseaudio] source.c:     device.buffering.buffer_size = "768000"
I: [pulseaudio] source.c:     device.buffering.fragment_size = "384000"

Take note the buffer_size and fragment_size values for the relevant sound card.

Calculate your fragment size in msecs and number of fragments (2/4)

Pulseaudio's default sampling rate and bit depth are set to 44100Hz @ 16 bits.

With this configuration, the bit rate we need is 44100*16 = 44100 is disabled and needs to be changed to 96000:

# sed 's/; default-sample-rate = 44100/default-sample-rate = 96000/g' -i /etc/pulse/daemon.conf

Restart pulseaudio to apply the new settings (4/5)

$ pulseaudio -k
$ pulseaudio --start

Finally check by recording and playing it back (5/5)

Let us record some voice using mic for say 10 seconds. Make sure the mic is not muted and all

$ arecord -f cd -d 10 test-mic.wav

After 10 seconds, let us play the recording...

$ aplay test-mic.wav

Now hopefully, there is no static noise in microphone recording anymore.

My Bluetooth device is paired but does not play any sound

See the article in Bluetooth section

Starting from PulseAudio 2.99 and bluez 4.101 you should avoid using Socket interface. Do NOT use:

/etc/bluetooth/audio.conf
[General]
Enable=Socket

If you face problems with A2DP and PA 2.99 make sure you have sbc library:

# pacman -S sbc 

Subwoofer stops working after end of every song

Known issue: https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/494099

To fix this, must edit: /etc/pulse/daemon.conf and enable enable-lfe-remixing :

/etc/pulse/daemon.conf
enable-lfe-remixing = yes

Pulseaudio uses wrong microphone

If Pulseaudio uses the wrong microphone, and changing the Input Device with Pavucontrol did not help, take a look at alsamixer. It seems that Pavucontrol does not always set the input source correctly.

$ alsamixer

Press Template:Keypress and choose your sound card, e.g. HDA Intel. Now press Template:Keypress to display all items. Try to find the item: Input Source. With the up/down arrow keys you are able to change the input source.

Now try if the correct microphone is used for recording.

Choppy Sound with Analog Surround Sound Setup

The low-frequency effects (LFE) channel is not remixed per default. To enable it the following needs to be set in /etc/pulse/daemon.conf :

/etc/pulse/daemon.conf
enable-lfe-remixing = yes

No sound below a volume cutoff

Known issue (won't fix): https://bugs.launchpad.net/ubuntu/+source/pulseaudio/+bug/223133

If sound doesn't play when Pulseaudio's volume is set below a certain level, try ignore_dB=1 in /etc/pulse/default.pa:

/etc/pulse/default.pa
load-module module-udev-detect ignore_dB=1

However, be aware that it may cause another bug preventing pulseaudio to unmute speakers when headphones or other audio devices are unplugged

Low volume for internal mic

If you experience low volume on internal notebook microphone, try setting:

/etc/pulse/default.pa
set-source-volume 1 300000

External links