Long term storage solutions for controllers and accessories

Any suggestions on this?

I ask because today I took out a couple of Gamecube controllers I had in storage and I don't know if it was because of humidity or what but the rubber on the sticks was kind of gooey.

I have them inside a madcatz hard carrying case, which is actually for consoles but I use it to store lots of controllers.

Other controllers were fine (SNES, Saturn, Wii, XBOX360) though I had also a Dualshock2 in there which was getting a bit gooey on the sticks as well.

I have a couple of silica gel packets inside the case, but really don't have a clue on why that happened.

 

Heat + Moisture. I have read that a wood box works best because it can breath and expand with heat. It always seems that the things I try to pack away nicely get funked and the things i throw in a drawer in the garage and forget about for years on end turn out fine. i dont get it.

 

Hmm, I see, good advice guys, I'll look into it.