First shower this year - drip,drip,drip. Sound of a little water behind the plastic shell. I had noticed that the pipe to the shower headr had popped off the tap body by a good few mm and just pushed it back without thinking. Now combined with drip,drip I reasoned that although I'd drained down the water the shower head forms a loop that will not drain unless the head is put on the floor. You have been warned. No all bad news - the shower cubical came apart very easily and I was able to remove the mixer tap and find where a joint had sprung and re-seal it. Thinking about it a bit more, even with the head on the floor the water could be lodged in the mixer body - maybe a blow job is needed as well.