Failing that, you should probably just turn the dehumidifier down a touch.
However, going too far the other way comes with its own problems...
I used to live 10 metres away from the sea in a flat above a hairdressers. As you can imagine, the walls were quite funky and actually had a 'rising sea salt' issue on them (when I reported the 'problem', the landlord told me it was all ok and even tried to get me to lick the wall, like it was a feature
Anyhow, after a few months of blasting the heating on with the windows constantly open to keep the mould at bay, most stuff that was against the wall would, when pulled back, show a big patch of mould on the wall and on the actual item that was against it, ruining several items, including some good books. Not only that, but some electrical items would blow when powered on (including some retro gear; by which time I threw in the towel and left).
Sounds like your place is a little bit like this.

