Room moisture is a real threat. Theres a lot of things that contribute to it too..... geography, the side of the house, air flow. I used to have my gear set up in a basement so this all reared its head to me. The cures all range in a huge expense curve. For the most part though, if you dont have moss growing on the walls or slicks on the floor you can buy powdered de-humidifiers. The sack of charcoal works, as does a few strategically placed open boxes of baking soda. Any hardware/home improvement store will also sell sacks of "absorbit" designed to get tossed and forgotten into a closet.