Bluetooth & Google Maps Voice Volume
 

I entered the address of a new restaurant in Google Maps in my iPhone and wow, the voice came blasting out of the speakers to tell me the route. My wife did a half a lane change in heavy traffic, not good. She wasn't happy. We finally got the volume lowered, I think by the steering wheel control, I'm not sure. What is the best method to control Google Maps voice volume? And incoming phone call ringing volume for that matter?

Side note: With my Bluetooth-enabled hearing aids, incoming calls now go straight to my phone, which is snug in my jeans pocket, instead of the car. My phone is iOS 12.1.1 but has been a problem since iOS 11. The workaround is to go to Settings > General > Accessibility > MFI Hearing Devices and turn Play Ringtones off. Calls come through the car then. Then when I leave the car I have to remember to turn Play Ringtones back on. The problem is not Acura's nor the hearing aid manufacrurer's, it's Apple and they say TS (tough situation).