PS: I've got this strange problem too

I've had in my car installed a Nokia handsfree-set one of the old ones. Now my navigation voice is not working bcoz i cannot hear it, MKIV shuts down the music but no voice allthought its enabled an its volume is high. I need to check which wires go where in that case too. I have allready started on dissasmebly the right glovebox and removed the Nokia unit.

Any idea how to double-check the voice cables too?