well i had another look myself, as it was baffling me as to why it was coming out the drain.
which, is only connected to the filter housing.
well it seems that a small amount of limescale which had formed around the filter seal, must have broken up after we put a calgon tablet in the machine........., thereby breaking the 15 year old seal.......
we had never used a limescale tablet before,and it was after using the calgon, that it started leaking, but didnt put 2=2 together
so....id say, im not going to use one again
i had a good clean around of the filter housing removed and cleaned up the seal, and now all is fine.
lets hope this was its only issue in 15 years, and it lasts another 15
Miele there great!