Can someone explain this phenomena to me?

…Ok, maybe it is not a phenomena exactly…

I will be sitting there, minding my own business, and suddenly, it’s like I will go almost deaf in one ear, and there is a loud ringing sound whose volume goes down gradually….and then my hearing is back to normal. (I do not have any hearing or balance problems of any kind, by the way.)

Is it my ear “resetting” itself or something? I know this must happen to other people.

This is my uber-interesting question of the day.