I used a signal splitter to split one coax cable signal out to two receivers. The problem I'm seeing after doing this is that both TVs that are receiving the split signal do not receive some channels. Prior to the split, they received all the expected channels, now they are not receiving certain channels and it's pretty much the same for both TV sets. I bought a signal amplifier and put it on the signal coming from the dish, prior to the signal splitter but it didn't change anything. Any thoughts or recommendations?