PipeWire: Difference between revisions

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{{Draft|The instructions below have not been thoroughly tested and may break things.}}
{{TOC right}}
[https://pipewire.org/ PipeWire] is a multimedia processing engine that aims to improve audio and video handling on Linux. Pipewire can act as a replacement for both [[PulseAudio]] and [[ALSA]] servers.


[https://pipewire.org/ PipeWire] is a multimedia processing engine that aims to improve audio and video handling on Linux.
== Prerequisites ==
 
* PipeWire requires [[D-Bus#D-Bus session bus|D-Bus session bus]] for most of its functionality.
* If [[Elogind|elogind]] is used, no further configuration is required.
** If [[Elogind#Verify_working_of_elogind|elogind is not used]], the user [[Setting_up_a_new_user#Group_management|should be added]] to <code>audio</code> group to access audio devices.
** Add <code>video</code> group, if you need to access webcam devices.
***{{Warning|Membership of the <code>video</code> group will also grant unrestricted access to video devices, which is often a security issue. See issue {{issue|15409}} for further details. }}
 
== Installation ==


== Prerequisites ==
The following packages i.e {{Pkg|pipewire}} and {{Pkg|wireplumber}} a session manager are the minimum required packages for getting pipewire to work.{{Cmd|# apk add pipewire wireplumber}}


=== Audio Group ===
=== Pulseaudio interface ===


When elogind is not available, the user has to be added to the <code>audio</code> group. The user must log in for this to take effect.
The package {{Pkg|pipewire-pulse}} allows pulseaudio applications to use PipeWire as audio server in the backend. {{Cmd|# apk add pipewire-pulse}}


<pre>
=== JACK compatibility ===
# addgroup audio <user>
</pre>


=== D-Bus ===
Since Pipewire replaces JACK, Install {{Pkg|pipewire-jack}} package, so it provides ABI-compatible libraries for JACK applications.{{Cmd|# apk add pipewire-jack}}


PipeWire requires a running [https://www.freedesktop.org/wiki/Software/dbus/ D-Bus] session. If you use a full desktop environment this will probably be started automatically, but with minimal window managers it must be done manually.
=== ALSA support ===


<pre>
Install {{Pkg|pipewire-alsa}} package to provide support for Alsa applications.{{Cmd|# apk add pipewire-alsa}}
# apk add dbus dbus-openrc dbus-x11
# rc-service dbus start
# rc-update add dbus default
</pre>


Then use <code>dbus-launch</code> whenever you start an X or Wayland session. For example:
=== GUI tools ===
<pre>
$ dbus-launch --exit-with-session sway
</pre>


=== XDG_RUNTIME_DIR ===
{{Pkg|pavucontrol}} or {{Pkg|pavucontrol-qt}} package provides a simple GUI app for controlling sound, outputs, etc. To use <code>pavucontrol</code> tool install {{Pkg|pipewire-pulse}} as the tool still needs [[#Pulseaudio interface|Pulseaudio Interface]]. The XFCE Audio mixer can also be used to help control volume by installing the package {{pkg|xfce4-mixer}} which is currently in available in [[Repositories#Testing|testing]] repository.


If you are not using a Desktop Manager, ensure that your <code>XDG_RUNTIME_DIR</code> is set to a user-writable location. By default for pulseaudio this is {{Path|/run/user/1000/}} or {{Path|/tmp}}. If this is not set, pipewire will create a directory in your home folder instead, called <code>~/pulse</code>, and on attempting to run Pavucontrol or pactl, you will get the following error:
''{{Pkg|qpwgraph}}''' is a graph manager dedicated to PipeWire with Qt GUI Interface.


<pre>
== Configuration ==
$ pactl list
Connection failure: Connection refused
pa_context_connect() failed: Connection refused
</pre>


== Installation and configuration ==
PipeWire and WirePlumber store their default configuration in {{Path|/usr/share/pipewire}} and {{Path|/usr/share/wireplumber}} respectively. If you want to edit the configuration, you need to move it to {{Path|/etc}}:


<pre>
{{Cmd|<nowiki># cp -a /usr/share/pipewire /etc
# apk add pipewire
# cp -a /usr/share/wireplumber /etc</nowiki>}}
</pre>


Create custom configuration file in <code>/etc/pipewire/pipewire.conf</code>:
=== Launch Pipewire  ===


<pre>
[[#Pipewire user service|Pipewire user service]] is the recommended method to launch Pipewire and will replace [[#pipewire-launcher|pipewire-launcher]]. Do '''NOT''' use both methods to avoid running multiple instance of pipewire.
# mkdir /etc/pipewire
# cp /usr/share/pipewire/pipewire.conf /etc/pipewire/
</pre>


Uncomment the following line in <code>/etc/pipewire/pipewire.conf</code>:
==== Pipewire user service ====


<pre>
Since [[Release_Notes_for_Alpine_3.22.0#OpenRC_User_services|V3.22]], Pipewire can be launched as a user service.  
{ path = "/usr/bin/pipewire-media-session" args = "" }
</pre>


Enable the <code>snd_seq</code> kernel module for ALSA support.
{{Note| Ensure the [[OpenRC#Prerequisites|Prerequisites]] are met and necessary [[OpenRC#Configure environment variables|environment variables are configured]] for using OpenRC user services before proceeding further.}}


<pre>
Issue the command {{ic|$ rc-status -Ur}} to view and verify the current user runlevel as '''gui''' and '''default''' for Wayland and Xorg, respectively, before proceeding.
# modprobe snd_seq
# echo snd_seq >> /etc/modules
</pre>


=== ALSA ===
To start the [[PipeWire]] user service, issue the command:{{Cmd|$ rc-service -U pipewire start}}
Verify that the above OpenRC user service is started before proceeding further: {{Cmd|$ rc-status -U}}
To enable the [[PipeWire]] user service, issue the command: {{Cmd|$ rc-update -U add pipewire}}


If you used neither Jack or PulseAudio nor intend to.
The above steps may be repeated for other user services, such as {{ic|pipewire-pulse}}, etc.  


<pre>
Note that the {{ic|pipewire-pulse}} service would be required to enable various functions, including setting audio levels with {{ic|pactl}} when [[PulseAudio#PulseAudio_Utils|running pulseaudio with pulseaudio-utils]] and to enable associated volume user keys.
# touch /etc/pipewire/media-session.d/with-alsa
</pre>


=== PulseAudio ===
==== pipewire-launcher ====


PipeWire can run a [https://www.freedesktop.org/wiki/Software/PulseAudio/ PulseAudio] daemon which should allow all existing PulseAudio applications to be used with the PipeWire backend.
{{Note|The pipewire-launcher script will be removed in the future to be replaced with [[#Pipewire user service|OpenRC User service]].}}


<pre>
Launch PipeWire by using the <code>pipewire-launcher</code> script. You'll probably get quite a few errors but just ignore them for now. {{Cmd|$ /usr/libexec/pipewire-launcher}}
# apk add pipewire-pulse
</pre>


It should be automatically enabled.
If .xinitrc is used, add {{Path|/usr/libexec/pipewire-launcher}} to your {{Path|~/.xinitrc}}.


=== JACK ===
If you do not use GUI by default, add the following stanza to your shell configuration file:{{Cmd|export $(dbus-launch)
/usr/libexec/pipewire-launcher}}


If you will be using PipeWire for [https://jackaudio.org/ JACK] applications install the required package and make system wide links to the PipeWire replacement JACK libraries (I have not had success using <code>pw-jack</code>). You will not need to start a JACK server.
=== Screen sharing on Wayland ===


<pre>
Applications which don't implement native Wayland screensharing rely on [https://github.com/flatpak/xdg-desktop-portal xdg-desktop-portal] plus the correct backend for your compositor. Screen sharing is known to work on:
# apk add pipewire-jack
* GNOME with <code>xdg-desktop-portal-gtk</code>
# ln -sf /usr/lib/pipewire-0.3/jack/libjackserver.so.0 /usr/lib/libjackserver.so.0
* KDE Plasma with <code>xdg-desktop-portal-kde</code> and Firefox
# ln -sf /usr/lib/pipewire-0.3/jack/libjacknet.so.0 /usr/lib/libjacknet.so.0
* Sway with <code>xdg-desktop-portal-wlr</code> and Firefox, see [[Sway]] for details
# ln -sf /usr/lib/pipewire-0.3/jack/libjack.so.0 /usr/lib/libjack.so.0
</pre>


{{Note|These symlinks might be overwritten during updates.}}
=== Bluetooth audio ===
{{Main|Bluetooth}}
* Enable PulseAudio support as described above
* Install bluetooth service packages: <code>bluez bluez-openrc pipewire-spa-bluez</code>
* Optional: install GUI manager for bluetooth <code>blueman</code>
* Enable and start bluetooth service: <code>rc-update add bluetooth; rc-service bluetooth start</code>
* Restart PipeWire
* Use commandline program  <code>bluetoothctl</code> or GUI program <code>blueman-manager</code> to scan and pair bluetooth audio devices.
* Use pavucontrol to adjust volume and manually select high definition bluetooth codecs.


=== Video ===
=== Video ===
Line 99: Line 91:
Video should work out-of-the-box with v4l2 devices (e.g. a lot of webcams) and [https://gstreamer.freedesktop.org/ GStreamer] applications.
Video should work out-of-the-box with v4l2 devices (e.g. a lot of webcams) and [https://gstreamer.freedesktop.org/ GStreamer] applications.


=== Screen sharing on Wayland ===
=== Realtime scheduling ===
 
You will need the right [https://github.com/flatpak/xdg-desktop-portal xdg-desktop-portal] backend for your desktop environment. Screen sharing is known to work on:
* GNOME with <code>xdg-desktop-portal-gtk</code>
* KDE Plasma with <code>xdg-desktop-portal-kde</code> and Firefox
* Sway with <code>xdg-desktop-portal-wlr</code> and Firefox


== Usage ==
For realtime scheduling, it is recommended to use {{Pkg|rtkit}} package. Add your user to the <code>rtkit</code> group.


Start the PipeWire media server. You'll probably get quite a few errors but just ignore them for now.
Alternatively, ensure your user has the right ulimit permissions. Since pipewire 0.3.66, you can add yourself to the <code>pipewire</code> group. You generally need (e.g. in {{Path|/etc/security/limits.conf}}):


<pre>
<pre>
$ pipewire
@pipewire - memlock 4194304
@pipewire - nice -19
@pipewire - rtprio 95
</pre>
</pre>


In a different terminal window check the default output device. I don't yet know how this default can be changed for all applications, so you'd better hope it's right!
This allows a member of the pipewire group to have the right permissions for PipeWire to use realtime scheduling without rtkit. This same snippet comes with pipewire since 0.3.66, so if you have a [[PAM]] login session and add yourself to the pipewire group, you don't have to do anything else. Note that the above {{Path|/etc/security/limits.conf}} will only work if your session is using [[PAM]].
 
=== Disable D-Bus support ===
 
{{Warning|This section is no longer supported since Alpine 3.19 as Using lua for configuration files is no longer supported in version 0.5.}}
 
For certain configurations (e.g. only audio playback and recording) D-Bus setup is not necessary and it can be disabled as follows.
 
Edit the following configuration parameters:
 
{{Cat|/etc/pipewire/pipewire.conf|<nowiki>context.properties = {
    ...
    support.dbus = false
}</nowiki>}}
 
 
{{Cat|/etc/wireplumber/wireplumber.conf|<nowiki>context.properties = {
    ...
    support.dbus = false
}</nowiki>}}
 
 
{{Cat|/etc/wireplumber/bluetooth.lua.d/50-bluez-config.lua|<nowiki>bluez_monitor.properties = {
  ...
  ["with-logind"] = false,
}</nowiki>}}
 
 
{{Cat|/etc/wireplumber/main.lua.d/50-alsa-config.lua|<nowiki>alsa_monitor.properties = {
  ...
  ["alsa.reserve"] = false,
}</nowiki>}}
 
 
{{Cat|/etc/wireplumber/main.lua.d/50-default-access-config.lua|<nowiki>default_access.properties = {
  ...
  ["enable-flatpak-portal"] = false,
}</nowiki>}}
 
== Testing ==
 
Use the <code>wpctl</code> utility from {{pkg|WirePlumber}} to test the working of pipewire: {{Cmd|$ wpctl status}}
 
=== pw-cat playback ===


<pre>
Test sound is working using an audio file in a format supported by [http://www.mega-nerd.com/libsndfile/ libsndfile]{{insecure url|Server refuses HTTPS connections}} (e.g. flac, opus, ogg, wav). Use <code>pw-cat</code> utility from {{Pkg|pipewire-tools}}:
$ pw-cat -p --list-targets
</pre>


Test sound is working using an audio file in a format supported by [http://www.mega-nerd.com/libsndfile/ libsndfile] (e.g. flac, opus, ogg, wav).
{{Cmd|$ pw-cat -p test.flac
$ pw-play /usr/share/sounds/alsa/Front_Center.wav
}}


<pre>
=== pw-cat recording ===
$ pw-cat -p test.flac
</pre>


If you have a microphone test recording audio is working.
If you have a microphone test audio recording is working.


<pre>
{{Cmd|$ pw-cat -r --list-targets
$ pw-cat -r --list-targets
$ pw-cat -r recording.flac
$ pw-cat -r recording.flac
(Speak for a while then stop it with Ctrl+c)
(Speak for a while then stop it with Ctrl+c)
$ pw-cat -p recording.flac
$ pw-cat -p recording.flac
}}
=== PulseAudio ===
Test PulseAudio clients using a media player, as most use PulseAudio.
=== JACK ===
Use <code>jack_simple_client</code> from {{Pkg|jack-simple-clients}}:
{{Cmd|$ jack_simple_client}}
You should hear a sustained beep.
== Troubleshooting ==
=== `wpctl status` shows no targets ===
First, check whether ALSA knows about your sound card using the <code>aplay</code> utility from {{pkg|alsa-utils}} package: {{Cmd|aplay -l}}
If sound devices are found, the issue is with your pipewire configuration.  Consider double-checking the instructions above. Otherwise, your sound card may not be supported in the version of the Linux Kernel you're running.  You should search online for fixes relating to your current kernel version and the codec of your sound card.  You can find each of these with:
{{Cmd|uname -r
cat /proc/asound/card0/codec* | grep Codec}}
Modern devices might require {{Pkg|sof-firmware}}, which is the case if you get <code>sof firmware file is missing</code> errors in dmesg.
=== Error acquiring bus address: Cannot autolaunch D-Bus without X11 $DISPLAY ===
Check and ensure that [[D-Bus#D-Bus session bus|D-Bus session bus]] is started along with your GUI session i.e. you are in a tty.
=== Connection failure: Connection refused ===
When using [[Wayland]], ensure that [[XDG_RUNTIME_DIR]] is configured correctly. If this is not set, pipewire will create a directory in your home folder instead, called {{Path|~/pulse}}, and on attempting to run Pavucontrol or pactl, you will get the following error:
<pre>
$ pactl list
Connection failure: Connection refused
pa_context_connect() failed: Connection refused
</pre>
</pre>


Test PulseAudio clients using a media player (most use PulseAudio) and if you use JACK test that too:
=== Bluetooth connect failed: br-connection-profile-unavailable ===


Ensure that [[#WirePlumber|Session Manager]] is running.
=== Play/Pause buttons not working on bluetooth headphones ===
Check {{Path|/var/log/messages}}. If you see something like this:
<pre>
<pre>
# apk add jack-example-clients
bluetoothd[3463]: profiles/audio/avctp.c:uinput_create() Can't open input device: No such file or directory (2)
$ jack_simple_client
bluetoothd[3463]: profiles/audio/avctp.c:init_uinput() AVRCP: failed to init uinput for WH-1000XM5
</pre>
</pre>


You should hear a sustained beep.
Then bluez is trying to register the headphones buttons as an input devices, but <code>uinput</code> is not loaded. Try <code>modprobe uinput</code>. If this works, see [[Architecture#Module_Loading]] for instructions on how to make sure this module is loaded automatically on each startup.
 
=== RTKit error: org.freedesktop.DBus.Error.ServiceUnknown ===
 
<pre>
mod.rt ../src/modules/module-rt.c:330:translate_error: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
mod.rt ../src/modules/module-rt.c:995:do_rtkit_setup: RTKit does not give us MaxRealtimePriority, using 1
mod.rt ../src/modules/module-rt.c:330:translate_error: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
mod.rt ../src/modules/module-rt.c:1000:do_rtkit_setup: RTKit does not give us MinNiceLevel, using 0
mod.rt ../src/modules/module-rt.c:330:translate_error: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
mod.rt ../src/modules/module-rt.c:1005:do_rtkit_setup: RTKit does not give us RTTimeUSecMax, using -1
</pre>


If you are happy everything is working, make PipeWire start automatically when your X or Wayland session starts. For example, you could add the <code>pipewire</code> command to <code>~/.xinitrc</code> or your window manager's config file.
Installing the {{pkg|rtkit}} package as mentioned in [[#Realtime scheduling|Realtime scheduling]] section resolves the above error message.


== See Also ==
== See also ==


* [[Bluetooth]]
* [https://gitlab.freedesktop.org/pipewire/pipewire PipeWire source repository]
* [https://gitlab.freedesktop.org/pipewire/pipewire PipeWire source repository]
* [https://gitlab.freedesktop.org/pipewire/pipewire/-/wikis/home PipeWire Wiki]
* [https://gitlab.freedesktop.org/pipewire/pipewire/-/wikis/home PipeWire Wiki]
Line 153: Line 238:
* [https://wiki.gentoo.org/wiki/Pipewire PipeWire on the Gentoo Wiki]
* [https://wiki.gentoo.org/wiki/Pipewire PipeWire on the Gentoo Wiki]


[[Category:Multimedia]]
[[Category:Sound]]

Latest revision as of 11:23, 11 August 2025

PipeWire is a multimedia processing engine that aims to improve audio and video handling on Linux. Pipewire can act as a replacement for both PulseAudio and ALSA servers.

Prerequisites

  • PipeWire requires D-Bus session bus for most of its functionality.
  • If elogind is used, no further configuration is required.
    • If elogind is not used, the user should be added to audio group to access audio devices.
    • Add video group, if you need to access webcam devices.
      • Warning: Membership of the video group will also grant unrestricted access to video devices, which is often a security issue. See issue #15409 for further details.

Installation

The following packages i.e pipewire and wireplumber a session manager are the minimum required packages for getting pipewire to work.

# apk add pipewire wireplumber

Pulseaudio interface

The package pipewire-pulse allows pulseaudio applications to use PipeWire as audio server in the backend.

# apk add pipewire-pulse

JACK compatibility

Since Pipewire replaces JACK, Install pipewire-jack package, so it provides ABI-compatible libraries for JACK applications.

# apk add pipewire-jack

ALSA support

Install pipewire-alsa package to provide support for Alsa applications.

# apk add pipewire-alsa

GUI tools

pavucontrol or pavucontrol-qt package provides a simple GUI app for controlling sound, outputs, etc. To use pavucontrol tool install pipewire-pulse as the tool still needs Pulseaudio Interface. The XFCE Audio mixer can also be used to help control volume by installing the package xfce4-mixer which is currently in available in testing repository.

qpwgraph' is a graph manager dedicated to PipeWire with Qt GUI Interface.

Configuration

PipeWire and WirePlumber store their default configuration in /usr/share/pipewire and /usr/share/wireplumber respectively. If you want to edit the configuration, you need to move it to /etc:

# cp -a /usr/share/pipewire /etc # cp -a /usr/share/wireplumber /etc

Launch Pipewire

Pipewire user service is the recommended method to launch Pipewire and will replace pipewire-launcher. Do NOT use both methods to avoid running multiple instance of pipewire.

Pipewire user service

Since V3.22, Pipewire can be launched as a user service.

Note: Ensure the Prerequisites are met and necessary environment variables are configured for using OpenRC user services before proceeding further.

Issue the command $ rc-status -Ur to view and verify the current user runlevel as gui and default for Wayland and Xorg, respectively, before proceeding.

To start the PipeWire user service, issue the command:

$ rc-service -U pipewire start

Verify that the above OpenRC user service is started before proceeding further:

$ rc-status -U

To enable the PipeWire user service, issue the command:

$ rc-update -U add pipewire

The above steps may be repeated for other user services, such as pipewire-pulse, etc.

Note that the pipewire-pulse service would be required to enable various functions, including setting audio levels with pactl when running pulseaudio with pulseaudio-utils and to enable associated volume user keys.

pipewire-launcher

Note: The pipewire-launcher script will be removed in the future to be replaced with OpenRC User service.

Launch PipeWire by using the pipewire-launcher script. You'll probably get quite a few errors but just ignore them for now.

$ /usr/libexec/pipewire-launcher

If .xinitrc is used, add /usr/libexec/pipewire-launcher to your ~/.xinitrc.

If you do not use GUI by default, add the following stanza to your shell configuration file:

export $(dbus-launch) /usr/libexec/pipewire-launcher

Screen sharing on Wayland

Applications which don't implement native Wayland screensharing rely on xdg-desktop-portal plus the correct backend for your compositor. Screen sharing is known to work on:

  • GNOME with xdg-desktop-portal-gtk
  • KDE Plasma with xdg-desktop-portal-kde and Firefox
  • Sway with xdg-desktop-portal-wlr and Firefox, see Sway for details

Bluetooth audio

  • Enable PulseAudio support as described above
  • Install bluetooth service packages: bluez bluez-openrc pipewire-spa-bluez
  • Optional: install GUI manager for bluetooth blueman
  • Enable and start bluetooth service: rc-update add bluetooth; rc-service bluetooth start
  • Restart PipeWire
  • Use commandline program bluetoothctl or GUI program blueman-manager to scan and pair bluetooth audio devices.
  • Use pavucontrol to adjust volume and manually select high definition bluetooth codecs.

Video

Video should work out-of-the-box with v4l2 devices (e.g. a lot of webcams) and GStreamer applications.

Realtime scheduling

For realtime scheduling, it is recommended to use rtkit package. Add your user to the rtkit group.

Alternatively, ensure your user has the right ulimit permissions. Since pipewire 0.3.66, you can add yourself to the pipewire group. You generally need (e.g. in /etc/security/limits.conf):

@pipewire - memlock 4194304
@pipewire - nice -19
@pipewire - rtprio 95

This allows a member of the pipewire group to have the right permissions for PipeWire to use realtime scheduling without rtkit. This same snippet comes with pipewire since 0.3.66, so if you have a PAM login session and add yourself to the pipewire group, you don't have to do anything else. Note that the above /etc/security/limits.conf will only work if your session is using PAM.

Disable D-Bus support

Warning: This section is no longer supported since Alpine 3.19 as Using lua for configuration files is no longer supported in version 0.5.


For certain configurations (e.g. only audio playback and recording) D-Bus setup is not necessary and it can be disabled as follows.

Edit the following configuration parameters:

Contents of /etc/pipewire/pipewire.conf

context.properties = { ... support.dbus = false }


Contents of /etc/wireplumber/wireplumber.conf

context.properties = { ... support.dbus = false }


Contents of /etc/wireplumber/bluetooth.lua.d/50-bluez-config.lua

bluez_monitor.properties = { ... ["with-logind"] = false, }


Contents of /etc/wireplumber/main.lua.d/50-alsa-config.lua

alsa_monitor.properties = { ... ["alsa.reserve"] = false, }


Contents of /etc/wireplumber/main.lua.d/50-default-access-config.lua

default_access.properties = { ... ["enable-flatpak-portal"] = false, }

Testing

Use the wpctl utility from WirePlumber to test the working of pipewire:

$ wpctl status

pw-cat playback

Test sound is working using an audio file in a format supported by libsndfile 🔓 (e.g. flac, opus, ogg, wav). Use pw-cat utility from pipewire-tools:

$ pw-cat -p test.flac $ pw-play /usr/share/sounds/alsa/Front_Center.wav

pw-cat recording

If you have a microphone test audio recording is working.

$ pw-cat -r --list-targets $ pw-cat -r recording.flac (Speak for a while then stop it with Ctrl+c) $ pw-cat -p recording.flac

PulseAudio

Test PulseAudio clients using a media player, as most use PulseAudio.

JACK

Use jack_simple_client from jack-simple-clients:

$ jack_simple_client

You should hear a sustained beep.

Troubleshooting

`wpctl status` shows no targets

First, check whether ALSA knows about your sound card using the aplay utility from alsa-utils package:

aplay -l

If sound devices are found, the issue is with your pipewire configuration. Consider double-checking the instructions above. Otherwise, your sound card may not be supported in the version of the Linux Kernel you're running. You should search online for fixes relating to your current kernel version and the codec of your sound card. You can find each of these with:

uname -r cat /proc/asound/card0/codec*

Modern devices might require sof-firmware, which is the case if you get sof firmware file is missing errors in dmesg.

Error acquiring bus address: Cannot autolaunch D-Bus without X11 $DISPLAY

Check and ensure that D-Bus session bus is started along with your GUI session i.e. you are in a tty.

Connection failure: Connection refused

When using Wayland, ensure that XDG_RUNTIME_DIR is configured correctly. If this is not set, pipewire will create a directory in your home folder instead, called ~/pulse, and on attempting to run Pavucontrol or pactl, you will get the following error:

$ pactl list
Connection failure: Connection refused
pa_context_connect() failed: Connection refused

Bluetooth connect failed: br-connection-profile-unavailable

Ensure that Session Manager is running.

Play/Pause buttons not working on bluetooth headphones

Check /var/log/messages. If you see something like this:

bluetoothd[3463]: profiles/audio/avctp.c:uinput_create() Can't open input device: No such file or directory (2)
bluetoothd[3463]: profiles/audio/avctp.c:init_uinput() AVRCP: failed to init uinput for WH-1000XM5

Then bluez is trying to register the headphones buttons as an input devices, but uinput is not loaded. Try modprobe uinput. If this works, see Architecture#Module_Loading for instructions on how to make sure this module is loaded automatically on each startup.

RTKit error: org.freedesktop.DBus.Error.ServiceUnknown

mod.rt ../src/modules/module-rt.c:330:translate_error: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
mod.rt ../src/modules/module-rt.c:995:do_rtkit_setup: RTKit does not give us MaxRealtimePriority, using 1
mod.rt ../src/modules/module-rt.c:330:translate_error: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
mod.rt ../src/modules/module-rt.c:1000:do_rtkit_setup: RTKit does not give us MinNiceLevel, using 0
mod.rt ../src/modules/module-rt.c:330:translate_error: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
mod.rt ../src/modules/module-rt.c:1005:do_rtkit_setup: RTKit does not give us RTTimeUSecMax, using -1

Installing the rtkit package as mentioned in Realtime scheduling section resolves the above error message.

See also