Comment 58 for bug 114053

Please, if you're accessing them from a question on Launchpad, tell us what number solved your problem, or tell us if your problem persists. This document is based on http://drowninginbugs.blogspot.com/2009/10/caveats-for-audio-in-910.html

[0] First of all, apply the updates, nothing more. Maybe your problem has already been resolved without you having to do anything else. Before following the guide and after updating, reboot and so aplicna you ensure that all changes.

[1] Make sure you are using the kernel and not the old Karmic. Run "uname-r". It should say 2.6.31-14-generic or higher. If you get an older version, you may be using an older kernel. Ask for your case.

[2] Make sure slmodemd is not running. Run "pgrep slmodemd. You should not give back anything. If you return something, ask about your particular case.

[3] Install linux-backports-modules-alsa-karmic-generic.
    sudo apt-get install linux-backports-modules-alsa-karmic-generic
Then reboot and see if the sound and run better. If he says that this package does not exist, go to System »Administration» Software Sources. In the Updates tab active "Unsupported Updates (karmic-backports)". Click close and when prompted if you want to reload package information say yes. Then try installing again.

[4] Add the PPA of Ubuntu Audio Development Team and maintained.
    sudo apt-add-ppa repository: ubuntu-audio-dev/ppa
    sudo apt-get update
    sudo apt-get dist-upgrade
Packages should be updated alsa and pulseaudio. then reboot and see if that fixes your problem.

[5] Get a PulseAudio log with these instructions: https: / / wiki.ubuntu.com / PulseAudio / Log
Get also a log of ALSA with these instructions: https: / / wiki.ubuntu.com / DebuggingSoundProblems # Automatic% 20sound% 20Information% 20Collection
Http://paste.ubuntu.com/ paste both logs in and passes the addresses to a question so people can see your particular case and try to help.