Hi Mike, I came across your problem regarding Incoming call volume too low,
Now, I don’t have your Head Unit or a Motorola phone, but I had a similar problem. I hope my solution could help, but no promises!
Try this one
Controlling Audio Volume
Using your Head Unit Menu button, look for a setting named Audio or similar.
What you need is a setting named Volume offset or similar.
A setting like this enables you to adjust all volume offset levels like Radio(FM/AM), AV-IN, DAB, USB, App/iPod(USB), and of course the Bluetooth volume offset level which could well be your problem.
Hope I could help!
Sid Wills
A satisfied Carsifi customer
I appreciate your thoughtful reply. The Alpine head unit has different volume settings for each input and the ‘Phone’ is already at maximum volume. I have tried turning down all the other input settings so the phone is higher relative to all the others but then I can’t get enough volume out of the others. I’ve tried to take it up with Alpine but the head unit is not one of their latest and greatest so that conversation has landed on deaf ears. The search for an answer continues. Thx again.
~ Mike
Also a satisfied Carsifi customer (except for this one issue)