Hi,
My Raspberry Pi overtime seems to be having some form of electricity on its metal usb shell bits, and getting really hot (though I'm more concerned about the electricution). My setup is using a RPi 3, Official TV uHat plugged into a rooftop aerial and connected to a USB keyboard, mouse and plugged into ethernet. My TV Aerial has a powered distribution box in the loft that was here when we moved in, and I have discovered that occasionally this one line seems to have power running through it occasionally.
Any ideas? Sorry if I haven't been good at describing lol