My local stations are in the Bangor, Me market, 20 miles away. My 622 dvr hasn't been able to add the NBC station to its OTA list despite a 92-94 power signal. I receive the local CBS and PBS affiliates and had been able to access the NBC station, but no longer able to. When I do a scan for the local chanels, it pauses at the NBC channel number 25, but will not lock it in. My brother across the street has access despite pulling in a signal strength in the 70's. I called Dish tech support, no help at all. I have unplugged, reset to no avail. Please help, I'm missing too much HD programming.