I have the Terk connected to my 612, it was working fine until last week. When I was viewing the Dish Network channels, and switched to the local tuned channels, the screen went out and was just flickering. There was a flickering black screen, but I was able to hear the audio. I had the DishNetwork guy come out today, and he changed the 612 to a new one. Was working fine, when I was testing it, and later tonight I switched to local channels again and the same problem again. I then realized the same thing happened nearly a week ago. So, I disconnected the Terk from the 612, and restore the 612 to factory default, removing all the local tuned channels, and now everything is working fine. Except now I can't use my Terk, any suggestions, or ideas behind what the problem could be, would be very helpful. Thank you.