Had a girlfriend who liked to play with ghost hunting apps on her phone. Pretty soon, things hanging or leaning against the wall would fall down and lights in the basement would turn on by themselves. Told her to stop fucking around with that shit, and if she brought home an oujui board (or however the fuck you spell it), it was going straight into the woodstove. Not saying I believe in it or not, but why tempt fate? The incidents stopped completely after we broke up and she moved out.