my wife has an 06 CTS. it has the XM radio, that in time became SiriusXM radio. Problem is the radio feed goes off & on. seems by the sound, that it’s an antenna issue. This now 11, almost 12 year old equipment, that it outdated. anyone else have the problem? is it the antenna issue? do you know of a fix for this? Has we all know, just about everything in this car routes through the entertainment center, and I’ve seen that replacing it, is a very tricky thing. don’t want to have to deal with the issues that will be created going aftermarket, bot to mention it would be very expensive. Thanks for any help offered!