I have an understanding of how bubbles work. They encapsulate air (or other fluids) in a membrane caused by surface tension. When they pop, there is often a sound. Sound is a type of energy, kinetic to be precise, that usually occurs from collisions. When a bubble pops I would assume that a sound implies that air rushes out due to a pressure change. Why is there a pressure change? I wouldn't expect the bubble to exert enough pressure to compress air. If the sound is caused by the air now being able to move into the rest of the room due to Brownian motion, then why wouldn't I hear air moving in a still room?
Perhaps I'm over-thinking this. Just curious. Thanks.