lol 'establishment of the root cause'...all you have to do is spray some WD40 down there to lubricate it. The regulator gets dry over time and produces a 'clicking' noise, it's pretty common. Mine has that problem. I have to spray mine every 2 months or so.

Also, the seals at the top of the door can get dry and need replacement if it's a squeaking noise. I've got that beauty now h: