[pulseaudio-discuss] pulseaudio-discuss Digest, Vol 13, Issue 46

[Drew]

On Mon, May 28, 2012 at 3:00 PM,
<pulseaudio-discuss-request at lists.freedesktop.org> wrote:
> The log just shows that the latency estimation that PulseAudio provides to
> VLC are unstable, showing a steep increase at nominal playback speed.
> If it keeps on happening all the time, something is clearly broken. It
> could be the audio hardware, the computer clock, the audio driver,
> PulseAudio or VLC. Being unable to reproduce your problem, I would not
> hazard a guess.

I've now confirmed identical behavior with mplayer (using SMPlayer as
front end).  It also happens with system sounds as well
intermittently.

> There are however a few things you can try:
> - Configure PulseAudio to use the same sample rate as VLC does with the
> "pure" ALSA output. If that works, the problem is probably with the audio
> hardware or the audio driver.

Done.  Both are currently set to sample at 48000.  No improvement.

> - Try with all power management *disabled* and no other active
> application, to rule out scheduling problems.

No other applications are running.  No change in symptoms.  I believe
power management is disabled, but will confirm again.

> - Check that your computer clock is running properly, with reasonable
> precision.

Confirmed to external clock over 1h, no drift noted.

> - Try with other file formats and codecs to rule out a VLC timestamping
> bug or corrupt input file.

Confirmed with multiple .avi, .mkv, .mp4, multiple files tested.

Many thanks for the response.  I'm more than happy to post logs/files
as needed to help someone more familiar with this issue debug the
problem.

D