exfm was a social music discovery site, which was acquired by Rhapsody on August 4, 2014. After that, everything was moved to archive.ex.fm.
Everything can be discovered through the sitemaps. The URLs in the sitemaps all point to ex.fm, which just redirects to the acquisition notice. However, changing ex.fm to archive.ex.fm will allow the content to be properly accessed from the public archive.