I just want to add that I've never had a good experience streaming from XM's feed. I don't know if it's flash-based now, but last I tried it was some sort of 64k WMA stream. The thing would work fine for a couple minutes, then it would have to rebuffer constantly.

Now, if I want to listen to XM at work, I log in to my slingbox and stream from my DirecTV receiver in audio-only mode. The audio quality is noticeably better and it never runs out of buffer.