[pulseaudio-discuss] underrun behavior with alsa-plugins

Maarten Lankhorst m.b.lankhorst at gmail.com
Tue Apr 19 09:12:23 PDT 2011

Hi all,

For wine I was investigating a bug with pulseaudio, it seems 
alsa-plugins' pulse driver ignores underruns. This is probably because 
an underrun will force you to call snd_pcm_prepare, this will destroy 
the stream and set up a similar new one again. This causes more 
susceptibility to underruns, so that code was disabled. However if I 
force underruns to occur, the state will stay running and it appears 
there is still some data left in the buffer, so sound stalls entirely. 
The latency gets updated to something like 0x7bdXXXXXXXXXXXXX which 
looks suspiciously much like a pointer to me, which may be a bug. If I 
instead make pulse_prepare call pulse_start on underrun, it's handled 
properly and sound will continue to work.

So my questions are.
1. Is the weird latency value update a bug? Digging it up I can only 
assume it's a bug in src/stream.c , but I haven't figured out why yet. 
Tested with pulseaudio.c
2. Any comments on this patch for alsa-plugins?

-------------- next part --------------
A non-text attachment was scrubbed...
Name: xrun.patch
Type: application/mbox
Size: 664 bytes
Desc: not available
URL: <http://lists.freedesktop.org/archives/pulseaudio-discuss/attachments/20110419/c760b945/attachment.bin>

More information about the pulseaudio-discuss mailing list