The best way to troubleshoot something like this is to mark all the individual pieces, or go by the serial numbers, and track the problem as you swap components. Fire it up at home, let it run until something happens. Then swap the caps on the bodies while keeping the bodies on the same Left/right channel.. The next time it happens if the problem moved it's the caps. If it stays on the same channel, then it's the body. BUT sometimes these things are seemingly random, and a single test can cause you to jump to the wrong conclusion, so you want to repeat the test if possible trying to get the same result.
Some mics don't like humidity. If you take them to an outdoor festival on a damp day they will act up, under normal use they won't. Put them then in a warm dry place and they will recover when they get damp. One thing to avoid in winter in colder climates is storing them in the car where they get cold, then you bring then indoors and set them up, where condensation will form. I had an LSD2 which didn't like humidity. I would have problems with it in Maine, then when I sent it to the Studio Projects in the California desert, they couldn't repeat the problem. On the 3rd trip they did, and replaced the capsules for free. If it's humidity related it almost surely the capsules. Keep in mind the vast majority of condenser mics were intended for use in a climate controlled studio, with on stage use secondary, and no one expected us to expose them to weather.