I just spoke with SiriusXM and they said this issue is on them and not GM. They are aware and are working on a fix and will issue credit for service but you will need to call them and complain. I am supposed to get an email back from engineering within 7-10 days. It stinks as the Sirius receiver I had in my cars since 2002 was spot on even in bad weather and never had 1 problem whereas this wears me out..
I am hoping help is on the way.