I have a 2008 a4, symphony audio (don't know what version), but the svc doesn't seem to work at all. More to the point, the bluetooth phone volume used to work, not it is so low the phone is unusable.

I've increased the volume on the steering wheel when the "bluetooth chime" occurs when the car is started, I've set svc and everything up to 5, all volume in the car is good except when you turn on the heater, the radio is drowned out and the phone volume of the caller is very low. the voice of audi is fine, however.

Any ideas