I installed a 3.5mm aux plug in-line between the radio and xm. I just select XM on the radio, plug the 3.5mm audio cable connected to any external music player. It automatically interrupt the XM signal and reroute to the external player. I just unplug the cable if I want to listen to XM.
I use bluetooth, you could eliminate the Kinovo and just use the aux however with the above setup I got:
Streaming music apps of the phone (local mp3, TuneIn Radio, Pandora,etc)
Spoken navigation (great with WAZE..."Police reported ahead")