Many years ago when my grandfather died in my late teens, for around a year after he died, the television would come on by itself at full volume in the middle of the night in the room he used to spend most of his time in. It would really creep me out. I lived with my mom and her parents, so I’d lived with him my entire life.
At night, I would usually watch the upstairs television, so wouldn’t be downstairs. The door was shut going into that room at night, no one was in there, no pets were in there to walk on a remote control, it was empty. Many times I’d be in bed reading, or watching the upstairs television and I’d hear something and go out into the hall to see what the noise was, and it was the downstairs t.v. on, at full volume. I discovered it on a number of times that way and my mother did as well.
One time I was talking to my mother about this and how much it bothered me, and it bothered her as well, and the next time the t.v. was found on, it was on mute. Lord, it was very creepy indeed. It stopped about a year after he died, but it was pretty spooky.