I have a factory NAV system out of a 05 Escalade and am trying to put it in my 05 Silverado. My truck came with the factory Bose 6 disc radio. I installed the NAV radio in my truck and had it programed to my truck. The radio programed but i get no sound. The tech tells me he cant get the radio to communicate with the amp. I tried the Escalade amp and it doesnt change anything. Has anyone made this change over and if so what di i need to make mine work?