Originally Posted by RoadTTripper
I believe that is some sort of an older style phone cradle. I have never actually seen one before. Usually there is just a filler piece that I use as a mini package shelf for my phone or such items. Don't know what actually mates up with it.
My 2011 roadster has a flat tray there and no "AUX" button. However, if you look in the tray corner nearest the AUX button, you should see an input for a audio mini-jack facing backwards. For a TT with the Concert stereos, you can plug in any audio device via this mini jack. If you use this jack, and if there is no CD inserted in the stereo, when you press the CD button on the stereo the stereo will light up as" EXT. Source" and play the music from the mini-jack. In your case, you may also need to do something with the AUX button.