We have the same problem, although it is hard to imagine that it is a hardware problem. We are missing only certain non-HD channels, mostly from 250 to 290. When we go to the HD version like from 291 to 691, the picture works great on HD. The exact same problem is on multiple TVs. How is it possible that the lower resolution signal has issues and the high resolution works fine. Not sure what to do. Any suggestions??
Thanks,