We have 2 TV's. One is a HD TV with a HD/PVR box attached and the other an older style TV with a digital box attached. Couple of days ago, both TV's started to display images all distorted and "digitized", and sound was affected as well. After a day off the digital boxes and using the cable only, I rehooked up the digital boxes. All was fine for about an hour or so, then it was back to the distorted digitized images and sound. Any idea of what is going on here?