I have been trying to wire an adapter for the 7-pin DIN plug on the 08 Vision console to accept a simple 3.5mm stereo jack for helmet speakers (no mic, just sound).  A couple of places sell them but they are for Wings, HD's and the pinouts are different.  I tried one and only get mono or single channel output with one speaker being nearly inaudible.  I know the pinouts on the console and have taken a 3.5mm jack apart and it has blk/red insulated copper wires and non-insulated silver (shield?).  I have tried splicing to the Left/Right speaker + pins on the DIN plug but lose bass and stereo.  I'm electrically challenged and am not sure what pins from the DIN should be wired to the exposed wires of the 3.5mm jack.  The Vision console only uses 5 of the 7 pins and they are Spk L +, Spk R +, Spk Common, Mic -, Mic +.  

JM makes a lower cord for their headsets with a 3.5mm plug added for earbuds, but they purposefully wire it for reduced output, so it is very weak with actual headset speakers and even with the Vision volume at max, it is still too weak, while the normal 7-pin output is full volume.  

I really think this is just a simple issue of wiring the correct pins to the 3.5mm but don't know which - I am not sure what the non-insulated wire of the 3.5mm should go to.  With just the L/R spkr wires connected to the pins, I get the audio on both sides, but it is mixed mono, not stereo and lacks bass which suggests a grounding issue.  Been at this a while and I'm likely not making sense anymore but would appreciate suggestions.

Here's a plug like what I am trying to do - although I am trying to splice and this is a single piece, but shows what I mean. 

I know this is an old thread, but does anyone know the part# for the part that connects to the Visions stereo and terminates in the 7pin DIN connector?

I want to connect the SENA adapter for the SM10 transmitter, hoping to get volume control from the handlebar to my SENA 20s headset.