Need some help on trouble shoot XM problems? The problem that I'm having is I can't receive any reception from my XM provider and I'm not in a black out spot for reception. Yes I have an active account; yes my On Star is active and can make calls; have checked the connection of the wiring harness for proper continuity at the XM and receiver module under the glove box. Are there any other areas I've missed that I can check to remedy this problem?