No more sound: how to investigate and repair?

[cactux]

Hello,

The sound was working without problem on Kubuntu 8.04, but since yesterday it does not work anymore. Before that, it used to work for months with Kubuntu 7.04. This 8.04 is a fresh install made a few weeks ago.
I noticed there was no sound anymore, so I closed all applications (sometimes it works, especially with flash applets in Firefox which lock the sound). But this did nothing.
So I restarted my KDE session: I had the startup sound! But no more sound after that.
After a complete reboot of the PC, there is no sound, even at the KDE session startup.

Here is what I tried to investigate this problem:
1. create a new user, added it in the audio group: no sound. So it is not a glitch in my profile.
2. started the live CD Kubuntu 8.04: I have sound. So the hardware is still ok.
3. checked with "fuser /dev/dsp" if a process is locking the device: nothing.

What can I try? I really would like to understdand what is going on, and to avoid doing a new installation.

For information:

lspci | grep Audio
00:1b.0 Audio device: Intel Corporation 82801H (ICH8 Family) HD Audio Controller (rev 02)

Thanks for your help
Yann

[dibl]

Re: No more sound: how to investigate and repair?

Follow the links in #6 here:

http://kubuntuforums.net/forums/inde...opic=3099811.0

[cactux]

Re: No more sound: how to investigate and repair?

Thank you dibl

I followed the link (this page http://ubuntuforums.org/showthread.php?t=205449), and tried to purge and reinstall alsa. No effect.
BTW: in this page there is an error, change the text "audio:29:root:moocow" by "audio:29:root,moocow".

According to this tutorial, next step should be to compile ALSA... but it was working before!

Any hint for the next step? (except reinstallaing Linux)

[dibl]

Re: No more sound: how to investigate and repair?

No no, I can't believe you would need to compile alsa, when it worked already.

Hmmmm. Have you looked up your chip on the alsa project site? I assume the snd_intel_hda module is the right driver, but sometimes they need an option for the model of computer that it's in.

aplay -l

should show the actual chip manufacturer.

Then look it up here:

http://www.alsa-project.org/main/index.php/Matrix:Main

and see what it says about the driver.