Using IP Bus with xm?
 

Hi all.
I am not sure if what I am thinking of is correct, but does my radio unit (has CAT button) in my 2006 HHR have the ability to connect a portable XM unit through the back?
I found this thread but no updates on it:
https://www.chevyhhr.net/forums/audio-video-17/need-some-help-4241/

Thanks in advance!