grey bar at bottom of screen

[Chezzy-Blade]

Hi, sorry if this has been asked before, ive had a search round but cant find an answer. so.
I have the Sony 46hx803, which is fed through a sony bdv-e380 surround system. there is a grey bar at the bottom of the screen about 10mm across the whole width. it is on every channel and seems to be on all settings.
can someone tell me what this is, is it a screen fault or a setting that I can change.
I cant alter the vertical position of the screen as its hdmi.. I think

thanks

G