border around screen (720p)

Hello,

Ive just moved house and setup all my kit again with the divx connected box in the bedroom.

Im hooking it up via HDMI running at 720p and I've noticed there is a 1cm thick black border around the edge of the screen, so the menu's/video isnt filling the screen fully. I've tried adjusting the resolutions and screen positioning but cant get it to fill.

Has anybody else experienced this or know of a way to fix it?

Thanks,
Dan