Ground balance from time to time. Keep the sensitivity on auto or low in the manual mode, swing it low and slow, and keep that coil cover off or keep it clean from salt water and sand. Also, remember, the coil and shaft are water proof, but not the housing it'self and Minelab doesn't cover water damage, so be careful, even if you put some kind of a plastic biggie over the housing.,,,,,,,,,, and remember what they said in Andy's book. Don't let the shaft get filled with water and then sling it over your shoulder to where the water drains down into the housing. BE CAREFUL, but at the same time, this is a really durable detector, so don't worry too much, just be careful of getting water in the housing. Marc. P.S. on the sensitivity thing, if your not having too many "spurious noises" you might try cranking up the sens a bit for more depth and sensitivity. Just realize that if it gets too high it can start giving you spurious noises, sometimes, and back it down again at that point. Marc.