Bibiana Bryson is an Argentine UFO researcher who has done a lot of digging into the Benjamin Solari Parravicini legacy, who's said to be Argentina's Nostradamus. She has a website that goes into more detail about his prophecies and exploits with ETs. The website is in Spanish but can be easily translated. In the video below she explains a bit more on what Parravicini saw for humanity's future. Much of his insights were allegedly inspired by direct contact with Nordic looking ETs. Nothing is mentioned about the strange sounds being heard worldwide. But the video was uploaded three years ago before the sounds were known to exist. The weird sounds are an Internet item that has something solid around it -- reality. Unlike other online conspiracies and unproven phenomena, such as reptilian humanoids or cloned figures of authority, these sounds actually exist where everyday people are experiencing them.
Additionally, Parravicini claimed that when these sounds begin to be heard they would herald the approaching time of transition, of change, a time of reckoning.