I have a strage issues in an RV, My duel reciever works great when I am not in a campground. Both TVs work great no problem. As soon as I get in an area where lots of RV's are my front TV still works fine but my rear TV get snow. Any ideas? Dish network says it is the cable but this seems crazy that it works well sometimes and others times doesn't. Both of my TV's are older, I was wondering if this could be the problem.