I'm having problems with my CZ-3D. It seems to have lost the ability to detect coins at any depth. When I test it by laying coins on the ground surface, it emits the "clanging" sound for any type of coin (very few high tones). When I bury coins at about 2 inches, I get no signal. I am concerned that maybe the electronics were damaged when I got caught in a downpour one afternoon. Some water may have entered the slotted port on top of the unit. I have tried all sensitivity settings, both enhance and salt, but with very little change. What options do I have if any other than sending it to Fisher for repair?