I had a problem like this with my fridge, but it flat out would not cool on power, worked great on gas.
Took it to the dealer Friday, they wanted to keep it there for 24 hours which could not did not happen.
It worked on gas just fine for the past two days, tried it on power here in SD. and for now is working darn good.
Dealer tech said everything was working as it should.
I am thinking there may be a problem but not a clue as to what.
A ghost in the machine.