Arch Linux

arghus

Member

Registered: 2023-01-25

Posts: 3

[SOLVED] Audio crackling with pipewire

Since my 1st arch installation there were always issues with audio crackling, but never figured out how to solve them..

I found some posts related, but got stuck at a point before the posts I found, which is when i journalctl | grep pipewire, I get this output, which keeps flooding the journal:

Jan 31 12:15:13 arch pipewire[1216]: mod.rt: could not set nice-level to -11: No such file or directory
Jan 31 12:15:13 arch pipewire-pulse[1218]: mod.rt: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
Jan 31 12:15:13 arch pipewire-pulse[1218]: mod.rt: could not set nice-level to -11: No such file or directory
Jan 31 12:15:13 arch pipewire[1216]: mod.rt: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
Jan 31 12:15:13 arch pipewire-pulse[1218]: mod.rt: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
Jan 31 12:15:13 arch pipewire[1216]: mod.rt: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
Jan 31 12:15:13 arch pipewire[1216]: mod.rt: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
Jan 31 12:15:13 arch pipewire[1216]: mod.rt: could not make thread 1221 realtime using RTKit: No such file or directory
Jan 31 12:15:13 arch pipewire-pulse[1218]: mod.rt: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
Jan 31 12:15:13 arch pipewire-pulse[1218]: mod.rt: RTKit error: org.freedesktop.DBus.Error.ServiceUnknown
Jan 31 12:15:13 arch pipewire-pulse[1218]: mod.rt: could not make thread 1222 realtime using RTKit: No such file or directory
Jan 31 12:15:14 arch pipewire[1216]: [0:00:12.167469519] [1216]  INFO Camera camera_manager.cpp:299 libcamera v0.0.3

I tried installing rtkit, which I uninstalled because it didn't change anything and also installed xdg-desktop-portal-kde, but have no idea how to use it and there is no service to start as xdg-desktop-portal-kde.

I'm running linux-zen, with X11 KDE and pipewire

Could anyone point me the way?

Last edited by arghus (2023-02-06 18:24:41)

Maniaxx

Member

Registered: 2014-05-14

Posts: 740

Re: [SOLVED] Audio crackling with pipewire

Probably PAM limits missing.

Configuring pam_limits (e.g. by installing realtime-privileges and adding your user to the realtime group).
https://wiki.archlinux.org/title/Professional_audio

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sys2064

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,871

Re: [SOLVED] Audio crackling with pipewire

You need to have rtkit installed and start it's service and restart pipewire (or just reboot...) for it to do anything. RT groups should not be necessary here, that's the point of rtkit.,

As for "no service", there is for all of these things (rtkit, pipewire, xdg-desktop-portal), but it's a user service not a system service: https://wiki.archlinux.org/title/Systemd/User

Last edited by V1del (2023-02-06 14:13:04)

arghus

Member

Registered: 2023-01-25

Posts: 3

Re: [SOLVED] Audio crackling with pipewire

Probably PAM limits missing.

Configuring pam_limits (e.g. by installing realtime-privileges and adding your user to the realtime group).
https://wiki.archlinux.org/title/Professional_audio

I'll try that, it may be the solution to the problem. Whenever a sound starts playing, it crackles and after it played something, it just works fine. The realtime may fix that.

You need to have rtkit installed and start it's service and restart pipewire (or just reboot...) for it to do anything. RT groups should not be necessary here, that's the point of rtkit.,

As for "no service", there is for all of these things (rtkit, pipewire, xdg-desktop-portal), but it's a user service not a system service: https://wiki.archlinux.org/title/Systemd/User

This one may solve the journal ctl issue, I'll try that too.

Thanks!

arghus

Member

Registered: 2023-01-25

Posts: 3

Re: [SOLVED] Audio crackling with pipewire

Problem solved! Still making the rest of the steps, but this already solved the crackling:

# echo 2048 > /sys/class/rtc/rtc0/max_user_freq
# echo 2048 > /proc/sys/dev/hpet/max-user-freq

Both were set to 64 before. Thanks!

Maniaxx

Member

Registered: 2014-05-14

Posts: 740

Re: [SOLVED] Audio crackling with pipewire

You need to have rtkit installed

If RLIMITS (rtprio, nice) succeed properly 'rtkit' shouldn't kick-in at all.
https://gitlab.freedesktop.org/pipewire … te_1503255

Last edited by Maniaxx (2023-02-06 18:31:09)

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sys2064

V1del

Forum Moderator

Registered: 2012-10-16

Posts: 21,871

Re: [SOLVED] Audio crackling with pipewire

I know, but if you didn't want to set the limits globally for any reason, for RTkit to do anything it would have to be started to set niceness to -11