I tried one of the newer ghost boxes that use echo feedback loops to create white noise. My apt building backed up to a cemetery and I was getting all kinds of communication. I started asking questions and got very specific intelligent responses. Total confirmation I was communicating with something on the other side. I started asking questions about 9/11 and got very interesting responses that basically confirmed my suspicions.
The next day one of the closed cabinets in the bathroom slammed close SUPER loud. Scared everyone. My cat has it's fur all fluffed out, tail straight up just staring at the empty bathroom. It was so freaky I've never done it since and don't recommend.