I suffer from it, mainly in my right ear. It is a ringing sound.
I usually don't hear it, but it will flare up once or twice a day and last for about a minute. It's more irritating than anything else.
The irony is that I think I'm 50% or so deaf in my right ear anyway. When I lie on my pillow at night, on my side, with the right ear up, I do not hear the traffic on the road. But when I have my left ear facing up, I can hear the traffic. That sounds quite hectic and sometimes stresses me out