I have experienced this sound, or lack thereof, several times, but of course, its always coursing through me, whether conscious or unconscious, along with everything else or nothing, for eternity.
Several Time 1: In the forest. There is no past present or future. Its beyond all that. Even beyond sounds. What is the sound of everything, everywhere all at once?
Several Time 2: When I'm in that circle again. Of course, I'm always in the circle again, Day/Night/Awake/Asleep, rinse and repeat. When I'm on entheogens, its as if every activity, person, life event I've ever had only existed in this space, and this space was completely empty and leads right back to here inescapably. Like everything we have ever done, thought or experienced is so much buzzing and the wings of a bee vibrating until they don't anymore. The silence that terrifies me.