E420i-A0 picture and sound keep going out

E420i-A0 When first turned on everything works fine for a few minutes. Then the screen will go black and the sound stops also. It will then come back on sometimes for a couple of minutes, and then go out again completely. I can then press the power button and the V will appear followed by HDMI-1, DIRECTV, in the upper right corner. Also "1080i" flashes on and off to the right of DIRECTV. No picture or sound appears. If I turn it off and leave it for a couple of hours, I can go through the same routine all over again. My thought is that one or more components on the boards is getting hot and breaking down. Any suggestions? Thanks