I have a 12-month old Pumptrol pressure switch attached to a pressure tank. Standard setting, unchanged, is 20/40, min/max. Recently, whenever a tap is turned on, even if only a dribble, the pressure switch cuts in and out rapidly (about 3-4 seconds) and the pressure gauge drops/climbs at the same rate between its min & max points. Clearly the tank can't be pressurizing / depressurizing so fast. I've made no changes to the settings and the contacts on the switch look very clean. I haven't been able to detect any leaks and suspect the pressure switch has a problem. Any ideas? Thanks