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bicyclingrevolution

Member

Registered: 2010-10-18

Posts: 71

(solved) Simultaneous output from Chromium and Pulseaudio

I need to be able to hear sound from my web browser and Pulseaudio applications at the same time, but Chromium isn't using Pulseaudio for playing Flash or any other sounds (like html5). Instead, Chromium takes over the sound device:

$ lsof /dev/snd/*
COMMAND     PID USER   FD   TYPE DEVICE SIZE/OFF NODE NAME
pulseaudi  8108 lion   16u   CHR 116,16      0t0 2024 /dev/snd/controlC1
pulseaudi  8108 lion   23u   CHR  116,7      0t0 6371 /dev/snd/controlC0
pulseaudi  8108 lion   28u   CHR  116,7      0t0 6371 /dev/snd/controlC0
pulseaudi  8108 lion   30u   CHR  116,7      0t0 6371 /dev/snd/controlC0
chromium  10696 lion  mem    CHR  116,4          6362 /dev/snd/pcmC0D0p
chromium  10696 lion   24u   CHR  116,7      0t0 6371 /dev/snd/controlC0
chromium  10696 lion   25u   CHR  116,4      0t0 6362 /dev/snd/pcmC0D0p

If I have any other application playing sound, I don't get any sound out of Chromium. And if Chromium is playing something, it blocks other applications, such as mplayer:

[AO_ALSA] alsa-lib: pcm_hw.c:1293:(snd_pcm_hw_open) open '/dev/snd/pcmC0D0p' failed (-16): Device or resource busy
[AO_ALSA] Playback open error: Device or resource busy
AO: [pulse] 44100Hz 2ch s16le (2 bytes per sample)
Video: no video
Starting playback...
A:   0.0 (00.0) of 527.0 (08:47.0) ??,?% 
Audio device got stuck!

Firefox exhibits the same behavior. Rekonq uses Pulseaudio, except when playing Flash (and then it has the same problem as Chromium). I can't really use Rekonq though because it is extremely slow to load websites.
I have pulseaudio-alsa installed. I am on a 64-bit system, and lib32-libpulse is installed.
My /etc/asound.conf:

# Use PulseAudio by default
pcm.!default {
  type pulse
  fallback "sysdefault"
  hint {
    show on
    description "Default ALSA Output (currently PulseAudio Sound Server)"
  }
}

ctl.!default {
  type pulse
  fallback "sysdefault"
}

# vim:set ft=alsaconf:


#The following was manually added for 5.1 upmixing
pcm.!dmix {
type plug
slave {
pcm surround51
channels 6
}
}
pcm.!default {
type plug
slave.pcm "dmix"
slave.channels 6
route_policy duplicate
}

I just need Chromium to play sound at the same time as Pulse applications. How can this be fixed?

              ~         ~         ~

Well, I guess I should have known the problem was with asound.conf. It looks like my ALSA configuration for 5.1 surround was taking precedence over the Pulse plugin. I replaced it with the recommended contents on the JACK wiki page. I realized I needed JACK as well, and fortunately there was an excellent walkthrough in the wiki! Chromium now shows up as "Chromium Alsa playback", and I can use programs that play sound from ALSA, Pulseaudio, and JACK, all at the same time.

Last edited by bicyclingrevolution (2012-10-14 23:05:14)