Strangeness.Nope, opening the door won't stop it! Good thought though. My old Prius definitely used the door opening to realize you were done with things like the headlights, which would otherwise stay on while you sat in the turned off car (and run the battery down).
I think we all see this happening:
Listening to phone audio, via bluetooth.
Stop the car. Turn off "engine".
Audio stops for a second, then resumes.
But since you are hearing audio even after opening the door, from the car speakers, that's super weird.
That said, I have seen some buggy behavior with certain podcast apps. For example, DownCast sometimes has trouble playing over bluetooth even though every other app and phone call is working fine over bluetooth. I wouldn't be surprised if your podcast app is having a strange interaction with the car.
Do other apps exhibit that same oddness? Or is it limited to one specific app?