I have an Ubuntu 12.04 machine hooked up via an ATI/AMD HD 6450 card through HDMI to my Sony HDTV. I am using a recent version of the proprietary fglrx / catalyst drivers from AMD. The audio goes along the HDMI.
When I change the channel or let my computer sleep I lose audio. Logging off and then back on makes it work again.
Any ideas what is causing the audio to drop?
Any ideas as to how logging off and then logging back in restores audio?
Is it possible to do the thing that logging off and then back in does wrt to audio via a command-line command?