Welcome to the forum @jeffro413.
There is a thread or two on connecting devices to the CTX audio system in the technical forums here. I recommend browsing through those to get some ideas. I don't think XM will connect via the USB plug since the audio system is looking for a specific file format related to music files on a mass storage device there. You might have more success with a BT adapter to tie your XM device to, and then connect the BT device to the bike via BT... unless your XM device already has BT. There are others here far more informed than I on BT and USB connectivity so far. I've only used an SD card in the USB connector with music files and that works great.