Yesterday I had 2 HR20s and AT9 installed. One unit has no problem viewing our local MPEG-4s, but our other unit randomly gets the "Searching for signal" pop-up and blacks out. It happened on the other HDs today. The installer says the signals great, saying the unit may be faulty. Here's my signal strength: Sat 101 Tuner 1 & 2: 97% Sat 110 Tuner 1 & 2: 76% Sat 119 Tuner 1 & 2: 98% Any tips? Should I tweek Sat 110?