Recently screen goes black, audio says on, if I let it sit it comes back. Then goes out again. If I turn it off for a bit, it comes back. Dish said get new HDMI cable. No change. The joey is fine. A Tech came out stayed 2mins and said his equipment never does that, it's my TV. Never touched a thing. But last night I watched REELZ for over 3 hours and it was fine. On REELZ for 90 mins tonight and it's fine. What's up? My late husband was a broadcast engineer for 30 years. Encluding a few at EchoStar unlink. I'm a bit lost & tech impaired, but I'm trying. Help.