Weird humming noise at home
I have found this a few times with incandescent lights and dimmers, most dimmers are SCR so they are turning on and off each cycle, the noise was actually coming from the element in the light, I did not quite believe it the first time I found this but figured it was because of the fancy shape of the chandelier lamps. A few years later I had it happen on some long life lamps the ones made to last 10 years with heavy filaments. And the last time was on a standard 60w clear lamp, all of these were on a dimmer and were quite noisy (I have poor hearing and could clearly hear them). So I would look at the lights as they may be the cause, change the level or turn off to see if it changes the noise.