Nasti

Thanks much - will check it all out when it's delivered. I see there are 3 mute wires on the 3100 power connect plus the yellow you used from the iso. I'm hoping one will trigger the mute w/ out needing to invert it, if not tag has me covered.

Do you recall if the mute is trigered by +12v on the concert HU?

PaulW

The mute function on all Audi radios that I have ever seen is an "open" circuit when not muted. When I say open, it's slightly different.

It shorts to ground when "mute" is engaged. It's not at ground potential when "unmuted", but then it is switched to the ground bus when "muted".

So essentially there is a ground bus (in the hands free device such as the parrot), then a switch that leads to the mute wire, which is open. When the Parrot mutes (or any other phone kit, they all work the same), it closes this switch and grounds out the mute.

By no means put 12VDC into the radio!!!!

Just cut the existing mute wire and hook up the yellow wire from the Parrot kit to it.

Same with the speaker wires, just cut them and hook up the parrot wires, it's just the wires coming from the open DB-25 in the back.

taga8

You can also turn off the mute inversion or microphone if you want (the board is jumpable).

Nasti

Your info and explinations are once again saving my azz!

I tore it apart last night. It looks like if I want to splice into the existing mic wire I need to go the the way of armrest / trunk / jumper - I could not find the stock mic wire behind the head unit with my beeping wire tracer. I may look further tonignt.

Thanks again++