Every so often a loud clicking sound was heard coming from the refrigerator. It sounded like a woodpecker was in the fridge. It was random, sometimes every five minutes, sometimes an hour or so. It only lasted a few seconds, so it was hard to find. Then I discovered that if I shut the climate control drawer off and back on, it would do it. Finally I noticed it was the bottom damper (two on mine) making the sound. It wasn’t that difficult to replace. There is a piece of foam that holds the damper in. I used a utility knife blade to carefully remove it. I sprayed some spray adhesive on the foam when I reinstalled it. Problem solved, woodpecker was evicted!