So we're having our first snowstorm here in WI... everything is coming in perfectly, even HD... except for the "old" HD channels in the 70's, which I can barely get a picture on. It's either a completely garbled and half-frozen image, or I get a no signal message. Which satellite would this mean I have a weak signal on? What other channels might this affect? Should I have them come out for a re-peak? Thanks for any advice!