When a tree falls and no one is around does it still make a sound?

Yes of course, but your probably referring to

"If a tree falls and nobody's around to hear it, does it make a sound"

Well nobody can ever know for absolute certainty, but if we get scientific about it, then yes.

Nobody has to be around to hear the noise it makes. It will make a sound, it won't just fall and be silent, it has to make a sound. Regardless of the fact that someone was there or not.