As I watch my Panasonic LCD rear-projection TV, the picture is fine. EXCEPT...when there is a lot of white background (sky, etc.), I notice what looks like finger prints and dust on the screen. Of course, the first thing I did was take some windex to the screen. But it turns out the screen is clean and I still see these "cloudiness." Is it possible that the INSIDE of the screen is dusty? Or perhaps something else? Anyone else have this problem and/or a remedy? I've had this set for 3 years and am reasonably happy with it, other than this problem.