They almost always quit communicating when the webs build up. The signal will noticeably reduce over days or a week until it's no longer able to connect to the wifi router. I like to blast spiders with a torch, so I'll hit the module with a brief fireball of flaming MAPP gas to clear the webs and it's all back to normal for a week or two.
Ever encountered this problem? This article suggests that the webs are conductive, but I'd never heard of that before, and never imagined it was possible until asking that question of the internet.
http://www.sciencedaily.com/releases/20 ... 113339.htm