Have a new Samsung 4k UHD HU8550 and Genie 44 with RVU. The picture stutters and audio cuts in and out. Lots of pixeling. The remote is very slow changing channels. DTV has had 5 different techs work on the system, at my house,  and finally said its the TV. Samsung tech changed the circuit board. NO change Samsung tech said if it happens again use your DVD and Apple TV to rule out the problem being the TV. Both worked great. Went back and used DTV and the problem is still there. Also, if I watch at "list" show none of the other TVs will work on list. Anyone have a fix?