Personally my thoughts on it are that the Sound is the result of uncontrolled creation magic, whether consciously created or more likely, sub consciously created, say by a dreaming individual. I think that the writers for XIV are likely to reference the old film, Forbidden Planet from 1956. Within that film a human scientist learns that a superior race of Alien, the Krell, once inhabited the planet he has been the lone researcher on, 200,000 years prior. They created a machine powered by 9,200 nuclear fusion reactors that was capable of constructing anything from their mere thoughts alone. The Krell apparently existed for over a billion years, and evolved past the point of war and violence. Yet, they disappeared, and all surface level structures of theirs on the planet were ground into dust in the span of a single night. "The secret devil of the soul of every person on the planet set loose all at once to loot and maim. To kill and take revenge." Within the movie, the professor who studies the Krell is shown to have gained their capacity at a limited scope to create with his mind, and he creates an intangible, invisible beast when he sleeps that seeks to destroy things that plague him in his waking hours.