George B
¯\_(ツ)_/¯
I have never seen this issue before.
James, it sounds like you are talking about RAP (Retained Accessory Power) which will allow the radio to keep playing for 10 mins after your turn the key off BUT that should turn off once a door is opened.
Before installing my Kenwood the RAP feature would turn off when ANY door was opened.
Now after installing the Kenwood, using the Maestro, it only turns off when you open the drivers door... which I like much better.
The RAP on this one shuts down by time out or by opening the drivers door only. Found that out last night too.