I would imagine that a crack associated with fasteners shearing would indicate an overall slipping of the panels down the roof, or the top face slipping in relation to the bottom face. That is certainly possible, especially if not enough fasteners are used to begin with, but would probably make some sort of noticeable structural effect (Deformed overhangs, cracked drywall, leaking roofing).

We don't really have enough detail from the OP to make any better observations. We need to know more details and patterns around the noise.
Another question... Is it a drywall ceiling or T&G?