This will be a quick post to outline a fix for something that we ran into this afternoon. My buddy herlo recently upgraded to Edgy and the sound had issues working after completion. After doing some digging we found a solution to the problem so I thought I would share this with the rest of you. This solution was found at the Kubuntu Forums.
This solution is to verify your user account is authorized to use sound (odd, I know, but its wise to check):
adduser [user] audio
Another solution that you can try is found at the Ubuntu Guide.
I hope either of these help anyone with audio trouble. They are rare–I haven’t had trouble with audio–but they happen. Enjoy!
Update: A comment has pointed out that I made an error in my original syntax for adding the user. I apologize if it caused trouble for anyone. The appropriate command is now listed above and offending command removed. Also, if you’ve made changes using the previous command you may want to use this command to see what changes were made and recover accordingly as it removed the user from groups instead of adding. My apologies.:
sudo diff /etc/group /etc/group-
(this will work as long as no additional changes have been made.)