I had a single TV box in my system (HD) and the system worked fine. I added a DVR two TV box and it set up fine but now both boxes will cause the system to cut in and out. The message I get talks about card not authorized and this is on both boxes TV's. Both boxes are authorized. If I disconnect the DVR the single works fine again. I did not try disconnecting the single to see if the DVR box worked okay. Dish said they think it is the switch, but that tests fine. Could it be the spliter? I check with someone else who has the same set up and they have the exact same switch and splitter with no issues. Sorry I don't have more specifics at this time. Any thoughts would be appreciated.