Caffeo CI powder behind drip tray

Hello all,

With my Melitta Caffeo CI, ground coffee powder collects behind the drip tray. In the picture it was just about two tablespoons.

Does anyone have any ideas?
Thank you and greetingsJingis

Has anything been done to the grinder? New grinding stones? Or did the problem come first?

Nothing was done to the grinder. I had once replaced the drainage valve. Of course, I had to take a lot of things apart. Can it be because of that? Grinder is the first for about 6 years.

It is difficult to see the grind in the picture. You can set the grinder times a little finer.
Over time, the grinding stones wear out. Then the powder becomes coarser and accordingly the amount can be more.