Same thing has just happened to mine and opened it up today. There is a device above the dispenser draw that determines where the water goes according to the settings (pre wash, main wash, conditioner, rinse) and what part of the cycle the machine is on. It is turned to the different settings by a small motor and 3 plastic gears and will be stuck and the clicking noise is the gear teeth jumping. It is probable that the gears will be damaged beyond repair. I have taken the gears out and permanently set the incoming water to the rinse setting - means we will have to put the powder in with the wash for now and can't use any of the fancy wash types, but it will work. Permanent fix is to get a new lid for the dispenser that comes complete with the rotating thingy, motor, gears etc - UK price £54 or so
q clark, November 2007