Hi, I own a Sony KDF-E55A20 TV that was diagnosed with a bad optical block by a repair shop because of a problem with green vertical straight lines about 1/2 - 3/4" inch wide evenly spaced across the screen. They also remain for 5-10 seconds after power down. In order to transport it back from the repair shop I had to lay it face down when I moved it from the shop to my home. After I got it home, I up righted it, plugged it in and it played perfectly all day. However, when I turned it back on later that night, the green lines returned. If the optical block was bad, why did the TV work fine for a while? I removed the back cover on the TV and rechecked all the connections and found them to be in tight. I also removed and thoroughly cleaned the optical block suggested in previous posts. I emailed Sony and their only suggestion was to unplug the TV and plug it back in to reset it but the problem is still there. All functions of the remote operate and I can bring up the on screen menu. On the diagnostics screen and there is no codes showing. The picture does play in the background of the lines and the channels do change. Do you have any suggestions on what to try next? If the opinion here is the optical block, I'll remove it and ship it to TSM for overhaul. It was suggested a possible Q block problem, but since I can bring up the on screen menu I would tend to rule that out. Thanks to all.