Does anyone know if it would be possible to fashion a switch to the 12 pin socket on the back of the radio? Something that would allow 2 accessories connected to it with a switch to go back and forth between the 2? If this is possible would it have any adverse effects on sound quality? What is a ballpark cost on something like that?

 

I use this: http://www.logjamelectronics.com/soundaux3.html and this: http://www.logjamelectronics.com/pietoy03aux.html . To get the result you are looking for. I have my Ipod and Sirius connected to the OEM Aux input. It will cost you about $130.