Since I got my X-1 probe, every now and then I would get falsing from it where it would loose sensitivity or start giving weak false signals in the air, that kind of thing. When I went to the beach, I realized what was causing it, where the wire goes in the top of it, with the plastic nut on it, I was getting sand in the threads the plastic nut screws onto. Once I brushed the sand out of the gap between the nut and threads, bamm, problem solved, worked perfectly afterword. Just use a stiff paint brush. Same thing too if your digging in wet mud or dirt, you will eventually get mud stuck in the gap between the nut and the probe itself, that mud or sand eventually must become magnetised and cause falsing just like between your coil and its cover. Simply brush it out with a stiff brush. On the beach I had to unscrew the nut (ON THE WIRE, NOT the one going into the probe) to get the sand out of the threads. Just remember not to over tighten, just finger tight.