My bedroom tv hates my 360! , but not the living room one....

[Barozi]

can't help you, but I've googled the problem and you're not the only one where a 360 doesn't really work with a Sony Bravia via HDMI.

http://forums.whirlpool.net.au/forum-replies-archive.cfm/1152764.html

http://www.avforums.com/forums/xbox-360/1200798-xbox-360-sony-bravia-hdmi.html

Though doesn't look like a general issue either.