Mine started ringing about 20 years ago, I noticed it at night and thought it was a transformer humming in the heater room on the other side of the wall from my bed until I noticed it while working on my dive buddies car :(
Not sure it’s related to diving even though I did blow out an eardrum on a dive in the early seventies. In the 60’s I was aircrew and then stationed with the 82nd. Airborne, raised a couple of teenagers, attended a few concerts and am still around aircraft so I can’t say it was caused by diving.
The military docs of course tell me it wasn’t caused by the military service!
I understand there is a pill for it but the side effects are a worse worry than the hum.