Update, checked today and 2 of the 5 base channels now show zero signal. My guess is the tuner keeps going out but how could this happen on 3 boxes?
What channels are you loosing? Their actual rf channel numbers and not their virtual channel numbers. I was loosing channel 10 and in my case it was cell phone interference that a lte filter solved. This might explain 2 channels, but not all channels unless you are very close to a cell phone tower.2 of the 5 base channels now show zero signal