I purchased a 2008.5 MS3 a couple years back and knew the PO had a subwoofer installed at some point. I also suspected he might have had an aftermarket HU that I've since confirmed.

I never really cared except that the AUX port in the center console didn't work (as well as the power jack). This past weekend I decided to yank out the radio to discover that yes, an aftermarket HU was installed at some point.

So here is what I saw:

Does anyone have a wiring diagram that would sort out the aux port? also in the photo is that three wires are spliced for a 1/16" headphone jack that could perhaps be for an AUX input?

Side project: Is there anyway to order the little piece that goes between the radio button and the membrane switch? It looks like so:

 

Definitely cant buy that little piece.

 

Well I measured one piece and am having a few made at shapeways.com so I hopefully solved that part.