Just got the BT kit from Kufatec for my A3 with Symphony/MFSW. Their wiring instructions say the grey wire for mute is only when installed with RNS-E system. Is this correct? So, there is no radio mute on the Symphony for incoming/outgoing calls?
The Symphony II has a Mute pin, so does the RNS-E. It has been mentioned (although not confirmed) that the RNS-E may mute over CAN. But you get definitely your Symphony muted when the mute wire is connected to the Mute pin.