I am using Ubuntu 10.10 and my sound stopped working. It had happened before and I had a vague recollection that reinstalling something worked so I did:
sudo apt-get purge pulseaudio
sudo apt-get install pulseaudio
sudo apt-get purge alsa
sudo apt-get install alsa
but now even the volume control icon is gone.
I also tried this later:
sudo apt-get --purge remove linux-sound-base alsa-base alsa-utils
sudo apt-get install linux-sound-base alsa-base alsa-utils
, but still the sound is not coming .
Best Answer
One possibility is is that your user account is not authorized to use audio devices.
"To resolve it, go to System → Administration → Users and Groups, select your user, click on the Advanced Settings button, enter your password, click the User Privileges tab and make sure the Use audio devices box is checked. While you're at it, do the same for the other users on your system."
Source: http://brunogirin.blogspot.com/2010/09/sound-issue-in-ubuntu-1010-beta.html