No Sound on Fedora 11 2.6.30 kernel (2.6.29 works fine)

[David Rosenstrauch]

On 10/11/2009 07:53 AM, Jerry Feldman wrote:
> Sound works fine on my system with the 2.6.29 (specifically
> 2.6.29.6-217.2.16.fc11.x86_64) kernel, but when they updated to 2.6.30
> the sound stopped working. If I reboot back to the 2.6.29 kernel things
> work fine. I've googled a number of different places (including Fedora
> Forum http://forums.fedoraforum.org/showthread.php?t=225660), but no
> luck. Looking at some of the issues it appears to be something between
> front and back speakers. My system only has 1 audio array . My sound
> card is nVidia Corporation MCP55 High Definition Audio (rev a2). I've
> looked through all the different settings and run various Pulse Audio as
> well as ALSA mixers. When I look at the Pulse Audio volume meter, in
> both 2.6.29 and 2.6.30 kernels, it does show the volume levels. So far,
> I don't see any clues at either boot time or in dmesg.

Some common sound issues I've run into with recent kernels:

* has one of the channels (e.g., master, PCM, front) been muted?
* has one of the channels (e.g., PCM, front) been set to volume 0?
* is the snd_pcsp module loaded?  (lsmod | grep snd_pcsp)  If so, unload 
it, and set it to not load.  (That's been known to interfere with other 
sound modules.)
* are any of the "Analog Loopback" switches turned on?  If so, turn them 
off, as they can disable sound.  (I tore my hair out over that one for 
quite a while.)

HTH,

DR