Unfortunately, I'm working with a college/community theatre, and in our space we don't have an audio team. All tech problems fall to myself, the tech director (who is great, but only on his second show with us), and the director, who is also great but doesn't have a strong grasp on sound/audio stuff.
The cables seem to be the only explanation left; since that's the one thing that we can't entirely check (they're in the ceiling, it would be a bear to get up to change all of them.) I'm in the process of begging for a new system.
Once again, thanks for all the input.