I have had a Bravia KDL 46Z5500 for the past 2 years and haven't had a problem with it. Recently however on most channels, only a 1/3 of the screen is visible as if zoomed in. The screen size button on the remote has no effect on it and I dont know how to chnage the image back to see the full screen. It happens randomly and is not present for all channels. Does anyone know how to fix this?