tinnitus_crazy

That’s easily tested though, right? As you can just change rooms and it’s gone.

I’ll definitely try, thanks! As a pre-measure, I won’t go to the living room for some time and closed the door, as it’s easier to test.

1) Yes, I do hear it away from home. I was thinking of it could be triggered by coil whine / high frequency noises like the router produces, then stays for some time and then gets re-triggered by the next coil whine.