My problem was with the large removable panel outside of the coach, directly behind the refrigerator, with 3 rows of vent holes. I'd say it is not likely to be your cause because my coach was
re-painted and
re-re-painted on a warranty claim. The first time was by the hacks at LongView RV. Then I was just fortunate to have it done right in the factory facilities. I'd guess masking of this nature is not used during original manufacture.
That said, it is certainly worth looking. The panel is held in place with 2 twisty-thingys. On the FCOC forum, there was a member who found paper plugging the ventlilation passage (to the roof), causing his fridge to perform eratically.
I
think temperature adjustments are made by sliding the white plastic "thingy" with the wire, on the aluminum fin (upper, right, rear of fresh food compartment) up or down. I would guess that lowering it would cause temperature to go down & raising it would increase the compartment temperature. Accidently moving it when you stock your groceries (or for Earl, when removing your beer) could cause changes in temperature.
Another thing to remember is there is no circulation fan. Putting warm foods or leaving the door open will take a long recovery time.
And Earl, I'm thinking you could get a 6-pack hidden in that compartment behind the fridge... accessible from the lawn chair, & hidden from the neighbors.