The charcoal filters have been installed the wrong way round.
![](https://cweb.miele.com/miga/All/90315589003__Print_All.png)
Install the charcoal filters with the surrounding edge downward in the holder; see image.
Black discoloration is visible on the rear panel inside the refrigeration appliance.
Install the charcoal filters with the surrounding edge downward in the holder; see image.