Tonya, you might be stating the obvious but your reminder is most appropriate.
I have two Sky boxes "in a cupboard" connected through a Global Combiner into an 8-way Global RF Distribution unit up in the roof space. Everything has worked beautifully for several months but recently, both boxes began spasmodically failing to respond to remote control from all of the Magic Eyes but continue to work normally when remote control is pointed directly at each Sky box. I have considered and tried all the obvious, except overheating and wonder if anyone can offer any more suggestions as to what might cause this?