I've just installed Ubuntu 12.04 on my Lenovo G550 notebook and decided to test the main thing I use it for, on Windows: watching movies and series on my living room TV.
Plugged in the HDMI cable, screen auto-configured nicely - awesome. But the sound is coming through my notebook's speakers, instead of my TV.
Searched for almost an hour on Google, found a couple of things - nothing that helped, though. Here are two links that made me sad:
On 2, David says that autoswitching was disabled... so how can I enable it?