I was in a bad car accident in February. The resulting concussion has left me with tinnitus that sounds like that. The other symptoms mentioned also fit concussion problems. Maybe the sounds out of the audible range caused a concussion of some sort? Just thinking out loud....
Tinnitus is treatable with cannibus. Give it a try.
I hear the exact same noise too. Fortunately it disappears when I stop thinking about it...........
We're surrounded by noise that we just naturally tune out. I live a half mile from a major six lane highway and when I go to bed, that's the only time I hear the traffic, but only briefly.
I grew up in northern Michigan and lived outside of town. I could go out in the back yard at night and when tuned into the surroundings, I could hear things creeping in the dead leaves, like worms and stuff. Pretty cool when you are focusing.......