Could be you've got your door adjusted TOO tight. The knife edge around the perimeter of the door opening on your stove is slightly curved outward across the top, so the door flexes slightly when you engage the handle, helping make a good seal. Up to a certain point, the tighter you adjust the door catch, the more the door will flex.
The ceramic glass doesn't flex, so if you overtighten the door catch, you can create tension between the door and the glass.
As the stove heats and cools, the three components of the door (cast iron door, glass, and the mild steel inner frame that holds the glass in place) all expand and contract at different rates. The assembly is designed to allow for this, creating a not-too-tight interface between the glass, inner frame and door, with flexible "glass gasket" to create an air seal between them. If the cast iron outer frame is flexed so far it creates tension against the glass, the varying expansion and contraction of the dissimilar materials could be causing the sound you hear.
If yours is a newer Summit, which has a black, 7/8" gasket, you don't need to tighten the door catch until you can't pull out the dollar bill. This is a low-compression gasket, designed to create a maximum seal with a minimum amount of pressure. A dollar bill should be held in place by the closed door, but not tightly pinched, as would be the case with the high-compression gasket PE used until recently (the new gasket is impregnated with graphite, which makes the seal at low pressure).
Try this: take the handle of a crescent wrench and pry the door catch open just a tad, and I'll bet the problem goes away.
