Are you plugged into shore power?
My only thought is the BIRD. The relay that connects or disconnects the chassis battery system with the house battery system. It has a time delay and a little controller to connect or disconnect based on charge state.
I really wouldn't think the thing would work with the store button engaged, but I'm not really certain how they wire that....
If not plugged in and it still happens......
either engine cooling noises?
or some kind of animal or insect?
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