Question about HopfenHöhle Beer cooler lift

I have the same "problem". Until now, I have simply aired it out. And occasionally wiping it out with a cloth.

I contacted Hopfenhöhle directly and have now received a new filter. Apparently they have a new type of filter...a rubber filter that replaces the traditional plastic filter. Maybe it is tight with it.

I can't find the video anymore, but I saw that they recommend cleaning the vent valve - especially if you use the cover with the artificial turf to make sure there is no dirt preventing the vent.

I also have to use a cloth from time to time.