The list is unfortunately very long (Wrong capsules, 1 times a month decalcification, despite high water hardness, milk container with stench .... etc.)
And now that it is also home for these systems (milk frother automatically) because it's just more important not to neglect the care of the machine ......
So it is always important to read the operating instructions very carefully, because as the most important care instructions are included that are as I said, even though it is very troublesome, be strictly adhered to.
A little tip: Before you set the coffee machine in operation, always check the pH value before the water, which can save a lot of problems. And so annoying it is for systems with the milk frothers too, always completely clean, if possible after each use (of course depends on the period between farms from)
Have fun!
PS .: Have my 7 year old Delonghi EN 90 now my mother's gift and I bought the Delonghi EN 680, my mother is also very enthusiastic, and was the funniest, she thought it would be a new unit :-)