I installed the USASpec “DF-TOY” auxiliary audio input device. It runs 2 audio sources into the CD changer input of the factory radio. You toggle back and forth between the two aux sources by selecting what “disc” is playing on the simulated CD changer. I set it up for my XM Radio as one input source, and the other an
ipod input jack. Works as advertised, great direct-wired audio quality, was only $60 bucks, and was very easy for me to install "plug and play" (and I'm not a techie). Here is a link:
http://www.usaspec.com/aux2.html
Good luck
Dave