I mostly just look for one that isn’t loose or hanging out of the wall, and I’ve never had anything weird happen. My sister did get a slow charge off one at an airport once and her cable got warm, so she unplugged it. Not sure if that was the port or her cable though.
I’d unplug it and give the prongs a quick look, just to rule out anything loose at the outlet. If that’s all fine, I’d probably just use it as usual and see if the click stays the same over the next few weeks. Mine’s been doing its little startup noise since day one and hasn’t changed.