I just recently purchased the Sony KP51WS510 (January 14th or so) and have noticed when the picture switches images, say going from a TV show to a commercial, for the black image that pops up for a second inbetween the top and bottom of the picture are lighter. This almost appears to be the same width of black bars that appear for some DVD's. I calibrated the TV with Ice Age's THX optimizer immediately after I purchased the TV and with Avia about a week after. I'm hoping this is just normal? Or do I already have a problem with the TV/burn in? Any tips would be appreciated as I can't find a similar situation while searching this forum.