My two and a bit year old KDL-46EX723 has slowly started to develop a yellowish horizontal band across the middle of the screen. It's pretty much the full width of the screen and about a quarter of the screen height, with indistinct edges. Most noticeable on white or very light images, particularly when there's vertical panning. Any ideas what this might be, is it a known problem with this model? A backlighting issue, a problem with the panel?
It's covered by a 5 year Marks & Spencer guarantee, so I guess I could get someone out to take a look at it.
