Yeah I had what I think is the same problem with my ADKs this summer.
Outdoor show, light rain on and off. Mics were under an umbrella, but it was really humid. Rolled for about 2.5 hours no problems. Then all of a sudden there is static and general weirdness in both channels for about 10 minutes of runtime, then it goes away again. My theory is that the humidity was not the the real problem, but rather some heavy clouds moved in and the temp dropped pretty fast and some moisture condensed in the mics, but that is just a guess.
I was running mic in, so there was only one set of cables involved. Did a visual and found no problems. Set everything up and really gave it all a workout pulling and twisting cables and could not make it happen again. And besides, it would be a pretty big coincidence for a two cable rig to have problems start in both channels at the same time, and problems in both channels go away about the same time.
Pretty sure what I had was a moisture problem not a cable problem, so it does happen.