I own a 2004 silverado with a 7 speaker bose sound system. I purchased a new deck and wanted to replace just the deck so i bought a wiring harness that is supposed to let me do this. I have rear audio controls that i was told i would lose. My problem is the deck fires up, discs are shown to be playing but i have no sound. I was told of a trigger wire that will turn the amp on which i found but the deck does not say anything about it. What do i do to get this amp to work. Thanks for any help. Eh!