Perhaps I need to study up on these if they're that directional. I am not losing my hearing. My hearing, according to tests, has always been "perfect" and the answer to "Well, why can't I understand people is noisy surroundings?" was always "Everyone has trouble with that." Not as much as I do. Eating with people in _quiet_ restaurants means that I can hear maybe one word in ten. (Add that to my food allergies and restaurant meals are an obstacle course.)
Recently modern technology has informed me that my ears don't process sound at the same rate (have I said this before? I've said it a lot since I found out) and that accounts for my trouble with background noise.
I will save that link.

Mary Anne in Kentucky