Can you record it? Sounds like maybe strong RF or electrical. Electric blanket or something that might be gathering and conducting RF energy?
Try it with your phones and all transmitters moved away, try it in a different room, experiment a little bit and see if you can isolate where it might be coming from.
Can you record it? Sounds like maybe strong RF or electrical. Electric blanket or something that might be gathering and conducting RF energy?
Try it with your phones and all transmitters moved away, try it in a different room, experiment a little bit and see if you can isolate where it might be coming from.