Mine did that. Call or email Winegard for tech support. They will walk you through troubleshooting the problem. Be sure your cable/cords are in excellent condition. Try a new shorter cord right at the receiver to eliminate that variable. Make sure to cable is rated for 3Ghz.
They had me take the cover off and use a multimeter to take some readings at various places on the control boards. I ended up shipping it back to them where they replaced a couple of components on the circuit board that had failed. Very few shops around that repair circuit boards but they make their own and know how to locate the problems. They usually send you a new set of cables but won't ship you old ones back unless you tell them to up front.
