This was too weird not to mention. An album called the “The CONET Project” at the archive.org that is, well, numbers being read over shortwave radio. The imagination (with, you know, good chemical additives) goes wild with speculation.
I could not resist listening to the Hungarian one (I happen to know the language a bit) and two things are obvious: it’s a kid reciting the numbers and it’s obviously been sliced together. Just plain creepy.
In a bit of linky-exchange Dave has a good write up with lots of related links.