I'm running Ubuntu 12.04. I have an LCD monitor that has built-in speakers which I use as my default monitor. I also have an LCD TV which I use as a second monitor sometimes to watch shows from the couch.
Both are hooked up to my graphics card via HDMI cables. I can get the displays to go into Twinview via NVidia X Server Settings, but I can't figure out how to get the audio to switch from the monitor speakers to the TV speakers.
There is no audio section in the NVidia settings, and the sound section in System Settings can only see my default monitor apparently.