After reading this thread and a bit of research, I'm very excited... Unfortunately I am a mechanical engineer and can't code. It certainly appears like someone could program this control into the Empeg which as another said would be priceless. I currently have a carputer with 7" monitor installed also and use it more for GPS and playing movies for my daughter than anything else. There are some changes I'd love to make to add more functionality on Empegface but alas don't know enough. Anyway, being able to control an XM setup with the Empeg would be more desireable than a temporary approach I am probably going to take - using the Carputer serial port and software and the line in on the Empeg.

I'm sure it's well known, but if not here is a link to some Windows front end software (mostly for cars) that has XM control in it.

http://www.frodoplayer.com/nuke/modules.php?name=Downloads&d_op=viewdownload&cid=1

If I could help anyone in any way with this project, let me know... I am hoping to buy the XM direct soon to integrate into my car system

Jemmi