I searched the forum for this particular problem but didn't find a concise answer, I also checked over at avs forum but to no avail. For the last year I recieved all my OTA HD channels via the Tivo perfectly. I have a terk 3x4 mulitiswitch that my large attic atenna runs into. Downstairs the line is split using a diplexer then going into the tivo. About a week ago my OTA channels started pixelating to the point only half a show would record. Heres what I've done so far... replaced diplexer at HD Tivo location adjusted antenna location per antennaweb bypassed terk 3x4 and diplexed only the one line I use got a 20db antennuator used a different antenna After I used the antennuator I got all of the locals in the soild 80-90 range with the exception of CBS which is on frequency 39. With this one channel in a 5 second span it will bounce from 80% to 10% to 70%. This is with the antennuator installed and running from 0db to 20 db reduction. There has been no new buildings put up in a four mile radius. My zip code is 73034. Thanks for any suggestions of other ideas I could try.