My GE frig runs constantly. Only 5 years old. Made a banging sound a few months ago, once. It has auto defrost. Freezer food is very frosty (snowy). Not dusty underneath. Checked temp controls. Did trouble shooting from booklet. Still nothing. Now the frig won't hold temperature, maybe 50. Freezer still frosty. Any suggestions?

Check the defrost timer. It should come on once a day or so. Defrost everything completely (well, not the food) and make sure the vent damper is moving freely and that air passages are not blocked.

I'm not sure what the banging sound could have been.