How do I stop water draining from the drain filter?

Miele Novotronic W844
Washing was a bit wetter than expected when I took a load out, thought the filter may need unclogging so took out and cleaned the drain filter (lolly stick, safety pin, small strip of plastic). Put next load in and had forgotten a sock so went back to the machine and there was water coming out of the bottom left, at the door to the drain filter. I have narrowed it down to the drain fixture, the little drain clipped onto the inside of the door that comprises of a plastic elbow and rubber tubing. Have experimented with pouring water into the soap dispenser drawer and it appears that the drain continues to drain even when the door is closed and the elbow is ment to raise up and stop the flow. I have removed the elbow from its housing on the inside of the door and even holding it up as far as the tubing will allow it still continues to drain water. I have ordered a new elbow (2-4 weeks delivery!) but as it does not appear to have any moving parts don't know if that will be the answer. Any suggestions would be greatly appreciated.