Back home, having succesfully used #Abetterrouteplanner to get me there and back. On #grapheneos with speech output. So it works, yay.
Now I just need to find out why it is so damn quiet when speaking. I mean, I have music running and it is perfect understandable. Then #abrp says something - this reduces the volume of the music considerably (good) and then talks. While inside a city and as such slow moving, I can hear it. Not good, but good enough.
Outside, with car going > 80 km/h, its so quiet, that one can't understand anything.
No, it does not help to crank up the volume. That will either blast the music annoyingly loud - or, if I do it manually for each notification, before that is effective the notification is finished...
Settings in app are set to loudest. Meh.
Other (routing) apps do not have this problem, and yes, the central speech output settings do say "Increase volume".