Stream xmradio from PC to Preamp

I am pretty sure that there are apps for Logitech Transporter and duet (not sure about SB and Touch) for XM and Sirius.

not sure about the airport route but you could use a digital to audio converter. use a usb out from the pc to input on dac. then rcas to aux input on the preamp. there are some affordable routes here. i have a hrt musicstreamer that does a great job for around 100 dollars. or you can spend as much as you want to get a better dac accordimg to your system.