@erkme73
Yes, the switches are pretty hot, and this should help, but humidity is a bad beast (here, eg. the fiber come into the box through a conduit that is directly connected to another underground conduit (D. 63mm), so, ... prevention is better than cure
I agree. My only problem is the desiccant packs would die of old age well before I'd remember to change them. Fortunately, my cat 5s come out of the conduit, go through some air, then through weather tight cable glands. Granted, unless the box is hermetically sealed, moisture WILL always get it, I'm banking on that it is condensate that does the harm - and so long as the internal temp stays above the dew point of the air inside, I won't see any.