I am trying to distribute the Comcast signal to the TV in another room via Monoprice HDMI Wall Plates, but it isn't working. There are two 50ft Cat6 cables between the wall plates. I've run a Sony BD over the lines with no problem. TV is a 55" Sony HX800. Comcast box is RNG100. Both LED's show solid red, but TV says no signal. Any ideas or suggestions welcomed.