I infrequently notice various rattles or squeeks in the top. They are not there in the AM but I hear noise at lunchtime. Or not at lunchtime but heard going home. It clears if I put the top down and back up again. I wonder if there is something in the design of the top that makes it "loosen" or tighten with temperature changes and a "restretching" during operation allows it to fix itself?

Guy