If a tree falls in the forest and no one is there to hear it, does it make a sound?
No. Of course not. This is neither a conundrum, nor a paradox, nor a mystery. Falling trees do not 'make' sounds, not even when red-shirted lumberjacks are there to hear them. When a tree falls, it displaces a large amount of air; the periodic rhythm of this displaced air then travels through the atmosphere in a manner akin to the ripples that move across the surface of a pond after a stone is dropped in. Only when this atmospheric movement strikes a human ear (or a microphone, which is merely a mechanical ear) is sound produced. A sound is how the human ear and brain perceive the periodic displacement of air. Sounds are 'made' by the human sensorium, not falling trees.
On a related note, consider this: You know that person sitting across from you on a blind date and babbling on and on tiresomely about his incredibly boring life? He isn't making a sound. You are.