alsa wheezing in an intel 82801G (ICH7 Family)

[Xisberto]

I can't remember if it occurred only after the update of alsa-utils (1.0.17-0ubuntu2 -> 1.0.17-0ubuntu3), but in the last week my sound card plays only wheezes and not the real song when I have alsa or pulseaudio selected. Using OSS the sound card works fine.

The complete line of lspci is:
00:1b.0 Audio device: Intel Corporation 82801G (ICH7 Family) High Definition Audio Controller (rev 02)

I'm using 8.10.

[Duane Hinnen (duanedesign)]

 Thank you for taking the time to report this bug and helping to make Ubuntu better. Unfortunately we can't fix it without more information. Please include the information requested from the "Reporting Sound Bugs" section of https://wiki.ubuntu.com/DebuggingSoundProblems as separate attachments.

Here is a very good Intrepid Sound Solutions post from the forum.
http://ubuntuforums.org/showthread.php?t=997506&highlight=configure+alsa
In the post markbuntu walks you through troubleshooting several audio/alsa problems. He also supplies a link to an even more comprehensive audio how to. the entire thread in general is a good resource for troubleshooting audio. I would also recommend possibly starting a thread on the forum to make certain this is not a configuration problem and is indeed a bug.
http://ubuntuforums.org/

[Xisberto (xisberto)]

Thank you for the help. I run the alsa-info.sh script and the result is located here: http://www.alsa-project.org/db/?f=0a36aaf7cce31049d181b3bba03d91adb7fbd7d1

The post from the forum is very nice, but it couldn't help. I'm afraid I used the wrong word in the report name, I tried to say, that I get noise instead of sound when I select to use PulseAudio or Alsa in System > Preferences > Sound. I get sound normally when I choose OSS.

I hope the info from alsa-info.sh help you.

[Andy Whitcroft (apw)]

On Wed, Dec 17, 2008 at 12:40:56PM -0000, Xisberto wrote:
> Thank you for the help. I run the alsa-info.sh script and the result is
> located here: http://www.alsa-
> project.org/db/?f=0a36aaf7cce31049d181b3bba03d91adb7fbd7d1
>
> The post from the forum is very nice, but it couldn't help. I'm afraid I
> used the wrong word in the report name, I tried to say, that I get noise
> instead of sound when I select to use PulseAudio or Alsa in System >
> Preferences > Sound. I get sound normally when I choose OSS.
>
> I hope the info from alsa-info.sh help you.

If it works in OSS and not pulse/ALSA, then its worth checking in your
alsa mixer to see if the PCM channel is at zero volume. If it is try
setting it to a sensible value like 80% and retest. We have had a lot
of cases where the report is you get 'crackling' only when sound is
produced if this is at 0, and normal behaviour if it is above 0. Could
you check and report back please.

[Xisberto (xisberto)]

Thank for you help. It was really the PCM channel, it was set to zero. I just can't understand how could it be, as I haven't done this. And also why it produces noise instead of zero sound.

Thank again!

[Andy Whitcroft (apw)]

On Wed, Dec 17, 2008 at 03:34:21PM -0000, Xisberto wrote:
> Thank for you help. It was really the PCM channel, it was set to zero. I
> just can't understand how could it be, as I haven't done this. And also
> why it produces noise instead of zero sound.

The loss of the PCM channel is something triggered during one of the
kernel upgrades. Not yet understood. The crackling is caused by a bug
in pulse audio which we expect to be fixed in the -proposed updates
block. But I am glad this is sorted for you.