When my system was installed one of m,y original receivers was an R15 dvr. I would ocasionaly get a searching for signal on 2 message, I called and they said I must have had a bad wire from the splitter so i swapped it and it was now searching on 1. I replaced that wire and it worked for a while then I would get searching for signal on 1 over and over and to resolve this I would unplug 2 and reconnect it and it would work for a few hours. I thought I must have had a bad dvr so I just got the HR21, new black HD DVR, and I have the same problem. Ideas?