This was supposed to be a hidden album which is linked to from various songs in Quarantine. If somebody clicked on the link, they will be presented with these 4 sound files which are less music and more an experiments in atmosphere.
The FM audio includes a sample from 96.7 FM mystery in Portland Oregon. Where people reported strange sounds happening sometimes on the radio station. Here is an LBRY link to a video about this mystery by Nexpo.
I don't think you think of Science Fiction often when thinking about Lars Von Trier. Yet, his 2011 masterpiece Melancholia is one of, if not the best, science fiction film(s) ever.