I have a 722 (18 months) with an OTA antenna on seperate coax to two TV's. The 2nd TV has only 1 coax input so installer ran DISH & OTA coax into a combiner so I could watch all of my locals on 2nd TV. All was fine for several months then the DISH channels became fuzzy unless I unplugged the OTA coax from the combiner & then they they returned to normal. I swithced between the 2 inputs with same result. The local signal stays great, only the DISH pic is affected. I tried replacing with 2 different combiners I had laying around but same result. As usual DISH tech was no help. Any helpful advice? Thanks.