Hello, I’m an electrician by trade. This is most definitely and ground issue, its most likely the ground wire is making a loose connection somewhere along the path between the electrical panel and the receptacle… Most common problem found when doing service calls… to be honest the “white” wire in 120v residential wiring is called a “neutral wire”, but it’s actually a ground wire also (in residential), with the only exceptions being inside light switch boxes, ceiling boxes for lights and fans, and 240v stove, dryer, and a/c receptacles where the white wire may be used as a power wire! The easies place to start will be inside your grills panel. After unplugging the grill from your power source, open up the panel and make sure the “Green Wire” inside there is properly connected on both ends. Actually tug on the wire, don’t just look. If you find a lug or screw connecting the wire to the body of the grill is a little loose or corroded, clean it tighten it ect. I repeat this is the most common electrical issue found when doing residential, and commercial service calls. If any part of this scares, cofuses, or just makes you feel uneasy, PLEASE CALL AN ELECTRICIAN. I hope you get it figured out because the “Ground Wire” is the safety mechanism, the part that cause a breaker to to flip off or a fuse to blow, to keep from killng someone, and if your getting a steady shock the safety is being bypassed. Therfore, IT’S OUT OF SERVICE! Electricity is nothing to play with. Get it looked at. Good luck.
Smoke On