Have a Mitsu 65511 and am now having visible scan lines during picture fade-in/fade-out and quick movement. Most of the visible lines occur in the center portion of the screen. This is while viewing non-HD cable signal through Scientific Atlanta cable box. My sharpness settings are not high, and I do not have any sort of picture filter on when these lines are seen. I have tested the image out with filters, and it doesn't really change. Lines are not as visible during DVD playback or HD playback. Actually, lines are non-existent in HD playback. I'm concerned about this because I don't remember seeing so many scan lines present when I first got the set about three months ago. What could be causing this? Thanks for any input.