macbook to tv via hdmi issue!

hi,
iv just switched from using mini dvi to vga, to hdmi. everythings running perfectly. but whatever display setting i have it on, the top centimetre of the screen is chopped off including the main task bar which is proving to be a bit of a problem lol! N e ideas?
thanks in advance
Mr Retouch!

http://www.mac-forums.com/forums/other-hardware-peripherals/193239-connecting-your-mac-your-tv.html

Check out Post # 2 - Item # 2