I have had a similar problem. When I opened up my shower unit (after switching off the electrics at the distribution unit) I noticed that a small part of the Hose Adapter had broken. Its where the water leaves the internals of the shower and enters the shower head hose. Basically it looks like this part ensures the seal between the cartridge and the shower head hose. So if broken the water pours down the inside of the shower rather than going into the shower head hose. I'm going to order a spare Hose Adapter for
sohit, June 2014