Kodiaqman

Hi All Have the 9.2inch Columbus. I have perused the 344 page owners manual but can’t see how to turn down the pre set volume of the ring for incoming calls over Bluetooth. Once answered, the call itself is perfectly normal volume...but the actual ringing is soooo loud! Whilst it is ringing I can turn it down by using controls on the steering wheel - but it then reverts back to a very loud ring volume for the next call. As I said the actual call itself is a normal volume, it is the very,very loud ring I am trying to lower. Grateful for any guidance.