Only some things. Like a TV or a speaker. Even when nothing is playing or they're muted, there's like this high pitched whine coming from them. A busted GPU in a PC makes a similar sound, though louder (coil whine). I sometimes feel like Quark that time he kept hearing shit in the shuttle with Odo and it turned out to be a bomb; hearing a faint thing no one else does until I pinpoint the source and turn it off.
One of the first times i tripped i saw all this purple dots coming off my tv that was turned off. It was very distracting, so i unpluged my tv and it faded away in like a minute.
I don't hear most of it consciously but I do feel the wave of comfort. It happens allot more now that I live rural. Lose power bout once a month for an hour, or two. It is just enough that you're still comfortable temperature.
I think it is mostly the Fridge. That thing loud AF and is always making noise.
Starting to wonder, I'm talking about hearing even electricity in the wires. It's hard to exactly explain it, but it's like a pressure on my eardrums and sensation in my head. It's not a distinct sound like a refrigerator, just a presence. There's different pitches for different devices too, oven burners are a low hum where led lightbulbs are a shrill whine.
It makes a sound before text messages or calls come in, sometimes other random clicking hissing sorts of noise? I almost always pick it up before any sound plays or vibration happens as a result. Constant sound? Not that I notice, but I'm around it 24/7