Originally Posted by JeffBurright
nearly every night I'll hear a single loud crack coming from the direction of either the deck, the side hull, or the window housing
I sail a fiberglas boat slathered with mahogany in its innards and (unfortunately) teak on the deck. Occasionally I hear a similar, "pop" that is the difference in expansion, or contraction between the dissimilar materials. Unless the "pop" precedes a frantic bilge pump, I'll bet your noise is from similar source.