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Set default input sources

List available input sources

$ pacmd list-sources | grep -e device.string -e 'name:'
name: <input>
 device.string = "hw:2"
name: <oss_input.dsp>
 device.string = "/dev/dsp"
name: <alsa_output.pci-0000_04_01.0.analog-stereo.monitor>
name: <combined.monitor>

To set it as the system wide default, add your source name to /etc/pulse/default.pa

set-default-source alsa_output.pci-0000_04_01.0.analog-stereo.monitor

For temporary use

$ pacmd "set-default-source alsa_output.pci-0000_04_01.0.analog-stereo.monitor"
Tip: The default source can be referred as @DEFAULT_SOURCE@ in commands, for example: $ pactl set-source-mute @DEFAULT_SOURCE@ toggle.

Set the default output source

Determine the name of the new source, which has a * in front of index:

$ pacmd list-sinks | grep -e 'name:' -e 'index'
  * index: 0
	name: <alsa_output.pci-0000_04_01.0.analog-stereo>
    index: 1
	name: <combined>

To set it as the system wide default, add the following to /etc/pulse/default.pa

set-default-sink alsa_output.pci-0000_04_01.0.analog-stereo

When done then you can logout/login or restart PulseAudio manually for these changes to take effect.

  • The sinks that are set as default are marked with * in front of the index.
  • The numbering of sinks is not guaranteed to be persistent, so all sinks in the default.pa file should be identified by the name.
  • For quick identification at runtime (e.g. to manage sound volume), you can use the sink index instead of the sink name:
    $ pactl set-sink-volume 0 +3%
    $ pactl set-sink-volume 0 -- -3%
    $ pactl set-sink-mute 0 toggle
  • To avoid unnecessary overriding of 100% normal volume it is better to use alternative utilities for managing of sound. See the forum thread for more information.
Tip: The default sink can be referred as @DEFAULT_SINK@ in commands, for example: $ pactl set-sink-volume @DEFAULT_SINK@ +5%.

Simultaneous HDMI and analog output

PulseAudio allows for simultaneous output to multiple sources. In this example, some applications are configured to use HDMI while others are configured to use analog. Multiple applications are able to receive audio at the same time.

$ aplay -l
**** List of PLAYBACK Hardware Devices ****
card 0: Intel [HDA Intel], device 0: ALC889A Analog [ALC889A Analog]
  Subdevices: 0/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 1: ALC889A Digital [ALC889A Digital]
  Subdevices: 1/1
  Subdevice #0: subdevice #0
card 0: Intel [HDA Intel], device 3: HDMI 0 [HDMI 0]
  Subdevices: 0/1
  Subdevice #0: subdevice #0

Or by using the the pacmd command:

$ pacmd list-sinks  | grep -e 'name:'  -e 'alsa.device ' -e 'alsa.subdevice '
	name: <alsa_output.pci-0000_00_1b.0.analog-stereo>
		alsa.subdevice = "0"
		alsa.device = "0"

The key to a configuration like this is to understand that whatever is selected in pavucontrol under Configuration > Internal Audio is the default device. Load pavucontrol > Configuration and select HDMI as the profile.

To setup the analog device as a secondary source, add the following to the /etc/pulse/default.pa configuration at the beginning, before any other modules are loaded:

### Load analog device
load-module module-alsa-sink device=hw:0,0
load-module module-combine-sink sink_name=combined
set-default-sink combined

Restart PulseAudio, run pavucontrol and select the "Output Devices" tab. Three settings should be displayed:

  1. Internal Audio Digital Stereo (HDMI)
  2. Internal Audio
  3. Simultaneous output to Internal Audio Digital Stereo (HDMI), Internal Audio

Now start a program that will use PulseAudio such as MPlayer, VLC, mpd, etc. and switch to the "Playback" tab. A drop-down list should be available for the running program to select one of the three sources.

Also see this thread for a variation on this theme and PulseAudio FAQ.

HDMI output configuration

As outlined in ftp://download.nvidia.com/XFree86/gpu-hdmi-audio-document/gpu-hdmi-audio.html#_issues_in_pulseaudio unless the HDMI port is the first output, PulseAudio will not be able to have any audio when using certain graphics cards with HDMI audio support. This is because of a bug in PulseAudio where it will only select the first HDMI output on a device. A work around posted further down is to first find which HDMI output is working by using the aplay utility from ALSA.

The original title for this section indicated the problem is specific to nVidia cards. As seen in this forum thread other cards are affected as well. The rest of the section will use an nVidia card as a case-study but the solution should carry over for people using other affected cards.

Finding HDMI output

Then find the working output by listing the available cards

# aplay -l
sample output:
 **** List of PLAYBACK Hardware Devices ****
 card 0: NVidia [HDA NVidia], device 0: ALC1200 Analog [ALC1200 Analog]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 card 0: NVidia [HDA NVidia], device 3: ALC1200 Digital [ALC1200 Digital]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 card 1: NVidia_1 [HDA NVidia], device 3: HDMI 0 [HDMI 0]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 card 1: NVidia_1 [HDA NVidia], device 7: HDMI 0 [HDMI 0]
   Subdevices: 0/1
   Subdevice #0: subdevice #0
 card 1: NVidia_1 [HDA NVidia], device 8: HDMI 0 [HDMI 0]
   Subdevices: 1/1
   Subdevice #0: subdevice #0
 card 1: NVidia_1 [HDA NVidia], device 9: HDMI 0 [HDMI 0]
   Subdevices: 1/1
   Subdevice #0: subdevice #0

Testing for the correct card

Now a list of the detected cards is known, users will need to test for which one is outputting to the TV/monitor

# aplay -D plughw:1,3 /usr/share/sounds/alsa/Front_Right.wav

where 1 is the card and 3 is the device substitute in the values listed from the previous section. If there is no audio, then try substituting a different device (on my card I had to use card 1 device 7)

Manually configuring PulseAudio to detect the Nvidia HDMI

Having identified which HDMI device is working, PulseAudio can be forced to use it via an edit to /etc/pulse/default.pa:

# load-module module-alsa-sink device=hw:1,7

where the 1 is the card and the 7 is the device found to work in the previous section

restart pulse audio

 $ pulseaudio -k
 $ pulseaudio --start

open the sound settings manager, make sure that under the hardware tab the graphics cards HDMI audio is set to "Digital Stereo (HDMI) Output" (My graphics card audio is called "GF100 High Definition Audio Controller").

Then, open the output tab. There should now be two HDMI outputs for the graphics card. Test which one works by selecting one of them, and then using a program to play audio. For example, use VLC to play a movie, and if it does not work, then select the other.

Automatically switch audio to HDMI

Tango-edit-clear.pngThis article or section needs language, wiki syntax or style improvements. See Help:Style for reference.Tango-edit-clear.png

Reason: Dodgy code, e.g. hardcodes DISPLAY (Discuss in Talk:PulseAudio/Examples#)

Create a script to switch to the desired audio profile if an HDMI cable is plugged in:

USER_NAME=$(w -hs | awk -v vt=tty$(fgconsole) '$0 ~ vt {print $1}')
USER_ID=$(id -u "$USER_NAME")

export PULSE_SERVER="unix:/run/user/"$USER_ID"/pulse/native"

if [[ $HDMI_STATUS == connected ]]
   sudo -u "$USER_NAME" pactl --server "$PULSE_SERVER" set-card-profile 0 output:hdmi-stereo+input:analog-stereo
   sudo -u "$USER_NAME" pactl --server "$PULSE_SERVER" set-card-profile 0 output:analog-stereo+input:analog-stereo

Make the script executable:

chmod +x /usr/local/bin/hdmi_sound_toggle.sh

Create a udev rule to run this script when the status of the HDMI change:

Note: udev rule can't directly run a script, a workaround is to use a .service to run this script
KERNEL=="card0", SUBSYSTEM=="drm", ACTION=="change", RUN+="/usr/bin/systemctl start hdmi_sound_toggle.service"

Finally, create the .service file required by the udev rule above:

Description=hdmi sound hotplug



To make the change effective don't forget to reload the udev rules:

udevadm control --reload-rules

You'll also need to reload the systemd units.

systemctl daemon-reload

A reboot can be required.

Surround sound systems

Many people have a surround sound card, but have speakers for just two channels, so PulseAudio cannot really default to a surround sound setup. To enable all of the channels, edit /etc/pulse/daemon.conf: uncomment the default-sample-channels line (i.e. remove the semicolon from the beginning of the line) and set the value to 6. For a 5.1 setup, or 8 for a 7.1 setup etc.

# Default
# For 5.1
# For 7.1

If your channels are not correclty mapped or the volume controls for the individual channels do not work as expected in pavucontrol, and you have a HDMI and an anlog soundcard, then try to add the following line to /etc/pulse/default.pa

load-module module-combine channels=6 channel_map=front-left,front-right,rear-left,rear-right,front-center,lfe

Note that this example is for a 5.1 setup.

After doing the edit, restart PulseAudio.

Splitting front/rear

Connect speakers to front analog output and headphones to rear output. It would be useful to split front/rear to separate sinks. Add to /etc/pulse/default.pa:

 load-module module-remap-sink sink_name=speakers remix=no master=alsa_output.pci-0000_05_00.0.analog-surround-40 channels=2 master_channel_map=front-left,front-right channel_map=front-left,front-right
 load-module module-remap-sink sink_name=headphones remix=no master=alsa_output.pci-0000_05_00.0.analog-surround-40 channels=2 master_channel_map=rear-left,rear-right channel_map=front-left,front-right

Make sure to replace alsa_output.pci-0000_05_00.0.analog-surround-40 with the sound card name shown in 'pacmd list-sinks'. Now you have 2 additional sinks which can be used separately. You can choose 'sink_name' freely, as long as there is no sink with that name already. The 'remix' parameter controls whether the audio should be down-/upmixed to match the channels in the sink.

Tip: If pulseaudio fails with master sink not found, comment out the remapping lines, start PulseAudio and verify your card output is set to the one you specified (e.g. analog surround 4.0). Alternatively, try using a sink index instead of a sink name.

Splitting 7.1 into 5.1+2.0

Similar to the example above, you can also split a 7.1 configuration into 5.1 surround and stereo output devices. Set your card to 7.1 mode, then add the following lines to /etc/pulse/default.pa:

 load-module module-remap-sink sink_name=Surround remix=no master=alsa_output.pci-0000_00_14.2.analog-surround-71 channels=6 master_channel_map=front-left,front-right,rear-left,rear-right,front-center,lfe channel_map=front-left,front-right,rear-left,rear-right,front-center,lfe
 load-module module-remap-sink sink_name=Stereo remix=no master=alsa_output.pci-0000_00_14.2.analog-surround-71 channels=2 master_channel_map=side-left,side-right channel_map=front-left,front-right

Make sure to replace alsa_output.pci-0000_00_14.2 with your sound card name, get it by running 'pacmd list-sinks'. This configuration will use the front/rear/center+lfe (green/black/orange) jacks for the 5.1 sink and the side (grey) jack for the stereo sink. It will also downmix any audio to stereo for the stereo sink, but will not touch the 5.1 output.

Tip: If pulseaudio fails with master sink not found, comment out the remapping lines, start PulseAudio and verify your card output is set to analog surround 7.1. Alternatively, try using a sink index instead of a sink name.

Disabling LFE remixing

By default, PulseAudio remixes the number of channels to the default-sample-channels and since version 7 it also remixes the LFE channel. If you wish to disable LFE remixing, uncomment the line:

; enable-lfe-remixing = yes

and replace yes with no:

enable-lfe-remixing = no

then restart Pulseaudio.

Binaural Headphones

ladspa-bs2bAUR provides a plugin to simulate surround sound on stereo headphones. To use it, find your headphones with:

$ pacmd list-sinks | grep -e 'name:'
	name: <alsa_output.pci-0000_00_1b.0.iec958-ac3-surround-51>
	name: <alsa_output.pci-0000_00_1b.0.iec958-ac3-surround-51.equalizer>
	name: <bluez_sink.00_1F_82_28_93_51>

Load the plugin (new sink_name is up to you, master=headphone's sink name):

pacmd load-module module-ladspa-sink sink_name=binaural master=bluez_sink.00_1F_82_28_93_51 plugin=bs2b label=bs2b control=700,4.5

Use pavucontrol to transfer streams to the new sink, or:

pactl move-sink-input $INPUTID $BINAURALSINKNAME

PulseAudio over network

One of PulseAudio's unique features is its ability to stream audio from clients over TCP to a server running the PulseAudio daemon reliably within a LAN. Ensure that client and server systems agree on the time (e.g. use NTP), or audio streams may be choppy or may not work at all.

To accomplish this, one needs to enable module-native-protocol-tcp.

TCP support (networked sound)

To enable the TCP module, add this to (or uncomment, if already there) /etc/pulse/default.pa on both the client and server:

load-module module-native-protocol-tcp

For this to work, it is a requirement that both the client and server share the same cookie. Ensure that the clients and server share the same cookie file found under ~/.config/pulse/cookie. It does not matter whose cookie file you use (the server or a client's), just that the server and client(s) share the same one.

Note: If experiencing trouble connecting, use (on server)

pacmd list-modules

TCP support with anonymous clients

If it is undesirable to copy the cookie file from clients, anonymous clients can access the server by giving these parameters to module-native-protocol-tcp on the server (again in /etc/pulse/default.pa):

 load-module module-native-protocol-tcp auth-ip-acl=; auth-anonymous=1

Change the LAN IP subnet to match that of the those clients you wish to have access to the server.

Zeroconf (Avahi) publishing

For the remote PulseAudio server to appear in the PulseAudio Device Chooser (pasystray), load the appropriate zeroconf modules, and enable the Avahi daemon.

On the client and server install pulseaudio-zeroconf.

On both machines, start and enable the avahi-daemon systemd unit.

On the server, add load-module module-zeroconf-publish to /etc/pulse/default.pa, on the client, add load-module module-zeroconf-discover to /etc/pulse/default.pa. Now redirect any stream or complete audio output to the remote PulseAudio server by selecting the appropriate sink.

If you have issues with the remote syncs appearing on the client, try restarting the Avahi daemon on the server to rebroadcast the available interfaces.

Selecting the Server

Run the graphical PulseAudio Volume Control pavucontrol. Under the Output Devices tab, you should see the local and remote output devices. Under the Playback tab, to the left of the "X" Mute Audio button, you should see a box containing the name of an output device. That box is actually a button, which will display a drop-down radio-button list of the available output devices, with one output device selected. Selecting an output device from the list will allow the audio stream to be switched to the PulseAudio server associated with that output device. This control is not at all obvious until you have used it, and is especially useful with a remote Headless sound server.

Similarly, under the Input Devices tab, local and remote input devices will be seen. And under the Recording tab, there will be a box, to the left of the "X" Mute Audio button, with the name of an input device which is actually a button which will display a drop-down radio-button list of available input devices.

Run pavucontrol on the local or remote host associated with the audio stream to be directed. For instance, run pavucontrol on the remote host to direct the remote audio output to the local host. Run pavucontrol on the local host to direct the local audio output to some remote host.

Setting up simultaneous inputs or outputs is a different thing. Search about "monitor" and "module-combine-sink" for that.

Switching the PulseAudio server used by local X clients

To switch between servers on the client from within X, the pax11publish command can be used. For example, to switch from the default server to the server at hostname foo:

$ pax11publish -e -S foo

Or to switch back to the default:

$ pax11publish -e -r

Instead of telling the PulseAudio server to stream audio (as described above), this will edit PulseAudio variables on the X11 root window, which will instruct the PulseAudio client libraries to connect to a PulseAudio server other than localhost. As such, the programs will no longer interact with the local pulseaudio process, which can then be stopped. Programs such as pactl, pacmd or pavucontrol will need to also run with the appropriate PULSE_SERVER environment/X variable to control the remote PulseAudio server.

Note that for the switch to become apparent, the programs using Pulse must be restarted, or their PulseAudio client library otherwise reinitialized (completely stopping and restarting playback may be enough). To make this setting permanent, edit default-server in ~/.config/pulse/client.conf or /etc/pulse/client.conf.

When everything else seems to fail

The following is a quick fix and NOT a permanent solution

On the server:

 $ paprefs 

Go to Network Access -> Enable access to local sound devices (Also check both 'Allow discover' and 'Don't require authentication').

On the client:

 $ export PULSE_SERVER=server.ip && mplayer test.mp3

ALSA monitor source

To be able to record from a monitor source (a.k.a. "What-U-Hear", "Stereo Mix"), use pactl list to find out the name of the source in PulseAudio (e.g. alsa_output.pci-0000_00_1b.0.analog-stereo.monitor). Then add lines like the following to /etc/asound.conf or ~/.asoundrc:

pcm.pulse_monitor {
  type pulse
  device alsa_output.pci-0000_00_1b.0.analog-stereo.monitor

ctl.pulse_monitor {
  type pulse
  device alsa_output.pci-0000_00_1b.0.analog-stereo.monitor

Now you can select pulse_monitor as a recording source.

Alternatively, you can use pavucontrol to do this: make sure you have set up the display to "All input devices", then select "Monitor of [your sound card]" as the recording source.

Monitor specific output

It is possible to monitor a specific output, for example to stream audio from a music player into a VOIP application. Simply create a null output device:

pactl load-module module-null-sink sink_name=<name>

In Pulseaudio Volume Control (pavucontrol), under the "Playback" tab, change the output of an application to <name>, and in the recording tab change the input of an application to "Monitor of <name>". Audio will now be outputted from one application into the other.

PulseAudio through JACK

The JACK Audio Connection Kit is popular for audio work, and is widely supported by Linux audio applications. It fills a similar niche as PulseAudio, but with more of an emphasis on professional audio work. It can offer lower latency audio monitoring along with greater control of input and output of multi-i/o sound devices.

The KXStudio method

This is the recommended method as it is officially endorsed by the JACK developers

This configuration works with both jack2-dbus and jack2 packages, but works better with the dbus variant.

JACK now has native features for bridging between ALSA, PulseAudio, and JACK. This will allow you to simultaneously have JACK and PulseAudio running with both outputting at the same time, with no config editing or terminal commands requried.

If you are using qjackctl, it is recommended to uninstall it before beginning this.

Begin by installing cadenceAUR from the AUR. Once installed and started, JACK bridge configuration is found in the bottom right of the window. The ALSA audio bridge should be set to ALSA -> PulseAudio -> JACK, and the PulseAudio bridge should be enabled. Make sure in pavucontrol that all output devices besides Jack sink are muted, and all input devices besides Jack input are muted. Start JACK using the Force Restart button, and if it starts successfully PulseAudio programs should begin outputting to JACK.

The manual sink configuration method

This configuration provides a method of allowing JACK and PulseAudio to run at the same time and output to each other. It uses manual configuration of the systems that bridge between JACK and PulseAudio. This configuration has no reliance on scripts or commands and is entirely based in configuration.

This configuration only works with jackdbus (JACK2 compiled with D-Bus support). It also requires the pulseaudio-jack package. Make sure that /etc/pulse/default.pa contains a line:

load-module module-jackdbus-detect options

Where options can be any options supported by this module, usually channels=2.

As described on the Jack-DBUS Packaging page:

Server auto-launching is implemented as D-Bus call that auto-activates JACK D-Bus service, in case it is not already started, and starts the JACK server. Correct interaction with PulseAudio is done using a D-Bus based audio card "acquire/release" mechanism. When JACK server starts, it asks this D-Bus service to acquire the audio card and PulseAudio will unconditionally release it. When JACK server stops, it releases the audio card that can be grabbed again by PulseAudio.

module-jackdbus-detect.so dynamically loads and unloads module-jack-sink and module-jack-source when jackdbus is started and stopped.

If PulseAudio sound does not work, check with pavucontrol to see if the relevant programs appear in the playback tab. If not, add the following to ~/.asoundrc or /etc/asound.conf to redirect ALSA to PulseAudio:

pcm.pulse {
    type pulse

ctl.pulse {
    type pulse

pcm.!default {
    type pulse
ctl.!default {
    type pulse

If it still does not work, check with pavucontrol in the playback tab and make sure the relevant programs are outputting to PulseAudio JACK Sink instead of your audio card (which JACK has control of, so it will not work). Also ensure that in the JACK graph the PulseAudio JACK Source is connected to the system audio output.

The shell script method

This method allows JACK and PulseAudio to output at the same time. It mostly relies on shell scripts that are automatically run by QJackCTL to manage aspects of how the JACK sinks and PulseAudio behave.

The basic idea is that killing PulseAudio is a bad idea because it may crash any apps using PulseAudio and disrupt any audio playing.

The flow of how this setup works:

  1. PulseAudio releases the sound card
  2. JACK grabs sound card and starts up
  3. script redirects PulseAudio to JACK
  4. manually send PulseAudio apps to JACK output (pavucontrol may come in helpful for this)
  5. use JACK programs etc
  6. via script, stop redirecting PulseAudio to JACK
  7. stop JACK and release sound card
  8. PulseAudio grabs sound card and reroutes audio to it directly

With QJackCTL, set up these scripts:

pulse-jack-pre-start.sh set it up as the execute script on startup script

pacmd suspend true

pulse-jack-post-start.sh set this one up as execute script after startup

pactl load-module module-jack-sink channels=2
pactl load-module module-jack-source channels=2
pacmd set-default-sink jack_out
pacmd set-default-source jack_in

pulse-jack-pre-stop.sh "execute script on shutdown"

SINKID=$(pactl list | grep -B 1 "Name: module-jack-sink" | grep Module | sed 's/[^0-9]//g')
SOURCEID=$(pactl list | grep -B 1 "Name: module-jack-source" | grep Module | sed 's/[^0-9]//g')
pactl unload-module $SINKID
pactl unload-module $SOURCEID
sleep 5

pulse-jack-post-stop.sh "execute script after shutdown"

pacmd suspend false

PulseAudio through OSS

Add the following to /etc/pulse/default.pa:

load-module module-oss

Then start PulseAudio as usual, making sure that sinks and sources are defined for OSS devices.

PulseAudio from within a chroot (e.g. 32-bit chroot in 64-bit install)

Since a chroot sets up an alternative root for the running/jailing of applications, PulseAudio must be installed within the chroot itself (pacman -S pulseaudio within the chroot environment).

PulseAudio, if not set up to connect to any specific server (this can be done in /etc/pulse/client.conf, through the PULSE_SERVER environment variable, or through publishing to the local X11 properties using module-x11-publish), will attempt to connect to the local pulse server, failing which it will spawn a new pulse server. Each pulse server has a unique ID based on the machine-id value in /var/lib/dbus. To allow for chrooted apps to access the pulse server, the following directories must be mounted within the chroot:-


/dev/shm should also be mounted for efficiency and good performance. Note that mounting /home would normally also allow sharing of the ~/.pulse folder.

PulseAudio selects the path to the socket via XDG_RUNTIME_DIR, so be sure to drag it along when you chroot as a normal user using sudo (see Sudo#Environment variables).

For specific direction on accomplishing the appropriate mounts, please refer to the wiki on installing a bundled 32-bit system, especially the additional section specific to PulseAudio.

Disabling automatic spawning of PulseAudio server

Some users may prefer to manually start the PulseAudio server before running certain programs and then stop the PulseAudio server when they are finished. A simple way to accomplish this is to edit ~/.config/pulse/client.conf or /etc/pulse/client.conf and change autospawn = yes to autospawn=no. Make sure the line is uncommented as well.

~/.config/pulse/client.conf #or /etc/pulse/client.conf

Now you can manually start the pulseaudio server with

$ pulseaudio --start

and stop it with

$ pulseaudio --kill

This setting is also respected by the default pulseaudio dektop session startup script start-pulseaudio-x11 which is executed from /etc/xdg/autostart/pulseaudio.desktop.

Disabling pulseaudio daemon altogether

To disable the pulseaudio daemon completely, and thereby preventing it from starting, one can add daemon-binary=/bin/true to the configuration file.

~/.config/pulse/client.conf #or /etc/pulse/client.conf

Remap stereo to mono

Remap a stereo input-sink to a mono sink by creating a virtual sink. It would be useful if you only have one speaker. Add to /etc/pulse/default.pa:

load-module module-remap-sink master=alsa_output.pci-0000_00_1f.5.analog-stereo sink_name=mono channels=2 channel_map=mono,mono
# Optional: Select new remap as default
set-default-sink mono

(replace alsa_output.pci-0000_00_1f.5.analog-stereo in the sound card name shown from pacmd list-sinks)

Switch player between virtual mono sink and real stereo sink.

Swap left/right channels

This is the same as "reverse stereo", where the left and right channels are to be swapped.

First, identify the card you want its channels swapped:

$ cat /proc/asound/cards

and use the name string for the device you wish to use (the one in square brackets, e.g. [Intel]).

Edit /etc/pulse/default.pa and comment out module-hal-detect and module-detect lines.

Search for the commented-out line that starts "#load-module module-alsa-sink", uncomment it and change it to

load-module module-alsa-sink device=hw:[device name] channel_map=right,left

Restart the pulseaudio deamon by running

pulseaudio -k; pulseaudio -D

Pulseaudio FAQ: How can I reverse my left and right speaker channels?

PulseAudio as a minimal unintrusive dumb pipe to ALSA

Some people do not want to run PulseAudio all the time for various reasons. This example will turn the full fledged audio server into an unobstrusive dumb pipe to ALSA devices that automatically starts and stops itself when done, allowing applications that requires PulseAudio to fully function while not touching any ALSA setting nor setting itself as the default ALSA device.

This configuration tells native PA clients to autospawn the daemon when they need it, then the daemon is configured to autoexit as soon as all clients have disconnected. The daemon itself uses a plain simple static configuration that uses your configured pcm.!default ALSA devices and nothing more. No replacement of ALSA's default, no playing with mixer levels, nothing but record/playback. Also make sure pulseaudio-alsa is not installed so standard ALSA clients don't default to pulse. alsamixer functions properly as well as any other ALSA clients. Also make sure common frameworks like Xine, Gstreamer and Phonon are configured to use ALSA: by default if they detect PulseAudio is installed they will try to use it before ALSA.

# Replace these with the proper values
exit-idle-time = 0 # Exit as soon as unneeded
flat-volumes = yes # Prevent messing with the master volume
# Replace these with the proper values

# Applications that uses PulseAudio *directly* will spawn it,
# use it, and pulse will exit itself when done because of the
# exit-idle-time setting in daemon.conf
autospawn = yes
# Replace the *entire* content of this file with these few lines and
# read the comments

    # Set tsched=0 here if you experience glitchy playback. This will
    # revert back to interrupt-based scheduling and should fix it.
    # Replace the device= part if you want pulse to use a specific device
    # such as "dmix" and "dsnoop" so it doesn't lock an hw: device.
    load-module module-alsa-source device="default" tsched=1
    load-module module-alsa-sink device="default" tsched=1 
    # Accept clients -- very important
    load-module module-native-protocol-unix

.ifexists module-x11-publish.so
    # Publish to X11 so the clients know how to connect to Pulse. Will
    # clear itself on unload.
    load-module module-x11-publish

Having both speakers and headphones plugged in and switching in software on-the-fly

By design, Pulseaudio automatically turns off Line Out when headphones are plugged in and uses Headphone slider instead. You can observe this behavior in alsamixer. What we want is to have Headphone and Line Out sliders working separately and at the same time. This is extremely useful if you want to remap Realtek's jacks to have, say, Rear Green for headphones and Blue for speakers (with the help of hdajackretask from alsa-tools).

To achieve this, you should directly edit Pulseaudio mixer's configuration.

1. We tell pulseaudio that headphones are always plugged in. Edit:



[Jack Headphone]
state.plugged = no
state.unplugged = unknown

Change no to yes

2. By default, Line Out's volume controlled only by Master, and not by Line Out slider itself. We want to merge Line Out with Master.

Add this snippet to the end of the file:

[Element Line Out]
switch = mute
volume = merge

3. We need to completely cut off Line Out when we use headphones. Edit:


Add this snippet to the end of the file:

[Element Line Out]
switch = off
volume = off

4. Like Pulseaudio, Alsa itself cuts off speakers when headphones are plugged in. Open alsamixer (in case of Realtek HDA alsamixer -c0) and change Auto-Mute mode to disabled.

5. Restart Pulseaudio

$ pulseaudio -k
$ pulseaudio --start

Now you have two separate ports on the same sink in pulseaudio. They mute each other, so you can switch to headphones and this will mute Line Out, and vice versa. To switch between ports you can use Gnome or Plasma sound mixer, or install appropriate desktop extension.

Allowing multiple users to use PulseAudio at the same time

It is sometimes desirable to run some programs as another user on the same desktop of the primary user in order to isolate the software. However, PulseAudio will not accept by default connections by the secondary users, since a PulseAudio daemon is already running for the primary user. However, a PulseAudio UNIX socket can be created in order to accept connections from other users to the main PulseAudio daemon run by the primary user.

First, edit /etc/pulse/default.pa or ~/.config/pulse/default.pa and add a directive for the unix socket to be created:

load-module module-native-protocol-unix auth-anonymous=1 socket=/tmp/pulse-socket

Afterwards, set PulseAudio as a client to the UNIX socket just created in the secondary user:

default-server = unix:/tmp/pulse-socket

Now, after restarting the PulseAudio daemon, applications running as the secondary user should be able to play sound through the main PulseAudio daemon running as the primary user without problems.