Is it just mine? I listen to a lot of podcasts and when using Apple CarPlay to send and receive texts, or take calls, the volume always defaults itself back down to 14 or 15 I think. Then I turn it up to around 23 and it stays until I change back.

i have tried with speed compensates volume both on and off and it still does it

radio playing at 23
incoming text at 15
turn up voice volume to 23
finish sending voice text
radio comes back on at 15