[pulseaudio-discuss] PulseAudio, Ubuntu 9.10 Karmic, SigmaTel STAC9200

Kyle Mallory kyle.mallory at utah.edu
Tue Sep 29 18:49:59 PDT 2009

I'm experiencing an odd problem with PulseAudio on Ubuntu Karmic 
9.10-a6.  I wasn't quite sure what was happening, but I made a video 
that hopefully better illustrates the problem.  I'm hopeful that someone 
can point me to a simple solution, or recommend a bug-fix.  There isn't 
any audio, which is fine, but in particular take note of what PulseAudio 
is doing to the ALSA mixer.


This is the problem I'm having on my laptop, with Karmic and PulseAudio 
on a SigmaTel STAC9200 audio chipset (Dell Precision M90).

When using the volume keys on the front of the laptop, the volume levels 
on the ALSA mixer adjust the Master first, and then after muting Master, 
subsequently adjust the PCM and LFE levels.

On my laptop, this results in very little volume control, and an overly 
bassy response as the LFE is maintained at full volume, while the master 
levels are dropped. Near the bottom of the volume range on the Notify 
window, the master volume is muted. Eventually the PCM and LFE levels 
are lowered through the last few 'presses' of the volume keys, and 
finally muted.

Any help, suggestions, or ideas would be appreciated.  I use my laptop 
for video editing, and a fubared audio mixer is really a deal-breaker.


Kyle  Mallory

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