Quote Originally Posted by Theozilla View Post
That has been answered already in Endwalker, the Sound/roar was all but literally stated to be due to Meteion’s Song of Oblivion.
Yeah, the 'sound beneath the earth' was sort of a symptom of the Ancients not really having means to interact with dynamis. Because they had no real grasp on what was happening, and had something of a geocentric, overly-rational worldview, the first thing to go wrong got misconstrued as the cause. It's a bit like if your car broke down, and you blamed it on the smoke that started coming out of the engine before it stopped.