Well yesterday I finally plucked up the courage to wire up my Nokia Carkit to mute my stereo when receiving and making calls.
I would like to say that I s*****d myself when I unplugged the stereo wired the yellow mute cable to pin 4 on the stereo (blue and orange cable) and plugged the connector back into the back of the stereo and the cd player started making a shuffling sound for about 30 seconds. I think this was a hard reset? Anyway it has been great since.
Anyhoos, it is working brilliantly, I would like to thank Duncan for providing the pin-out colour (in another forum) and Scarface for his contribution as well (in another search I did).
If your thinking of doing this I would advise you to do it, I am no electrician and managed to wire up the mute cable no problems. In hindsight I did cut the cable and use plugs to wire the cables together but I don't think you need to do that as there is sufficient space to plug the yellow mute cable in directly into pin4 (I would recommend you use a hard cable to do this (household electrical type) as it is much firmer to plug in.
Anyway, hope that all makes sense - now I will never miss a call!
Shame it doesn't pause the CD player though, well can't have everything!
Cheers guys!