While hunting in the sand at the beach yesterday, I noticed in 2 different spots, my detector started going nuts, display flashed erratically, entire readout blanking on and off etc. also very odd choppy low pitch / weird tone combo. It is almost like it couldn't identify the target so it threw a tantrum. What type of metal or object would cause this. As soon as I moved away, everything worked fine. I wish now that I would have dug it, but I dug so many holes yesterday, I just decided to move on.