Navigation voice on iPhone too quiet volume low

As below I found the same problem on an iPhone7 using Google maps. It looks like the Google Maps App is missing an iPhone compatible volume control. The work around I found was to open a different app, increase the in app volume in the other app to something loud enough to navigate with and then go back to Google Maps. That seemed to fix it.

Navigation voice on iPhone 11 extremely low

I can barely hear the navigation voice on my new iPhone 11, while Google maps is nice and loud. The navigation voice on my old iPhone 6 was good and I used it all the time. Now, I have to use Google maps. Settings for navigation voice in Maps is already set at the loudest option, but it doesn’t work. It’s too low to be functional while driving. Any ideas how to fix this?