Hello, can anyone help with this. I have 3 joeys that only give a black screen. I have had 2 techs out, 1 was there 8 hours, the cables were changed out, hoppers, joeys and nodes. I was told by the last tech that was out that one of my electrical jacks showed reversed polarity so I paid an electrician to come out and it was one jack showing that and now my joeys still dont work. I have 2 hoppers with sling and 3 joeys. I've switched where they plugin at and i get video for maybe a minute then it starts looking for hopper/sling again. I can still see the menus. I dont want to go back to 722k but i may have to my son has been without his tv for 12 days.