In response Johnny Five to his Publication
The Hum - Wikipedia
https://en.m.wikipedia.org/wiki/The_Hum
Check this out. I've been hearing it for years. So annoying
Same, been hearing it for years intermittently. Becomes almost debilitating.
In response Johnny Five to his Publication
I use a floor fan at night to drown out the sound so I can sleep.
Occasionally I can feel the vibration from it. Very subtle. Therefore I think whatever it is moves. Cant tell what direction its coming from so its either coming from above or below.