In my experience, the browser opens and plays the audio files on another tab instead of directly downloading. For a long time now, I've put up with this by right clicking and selecting "save audio as..." OR opening the page info and downloading the file from the list of medias; but there are some sites that doesn't allow this (like hive.co right now). Selecting "save ausio as..." again defaults to an .htm file, and selecting "all files" and downloading it as "file.mp3" only yields an unplayable file. As I've observed this problem occurs where the url doesn't end with the file format e.g. "site.com/file.mp3/lkjdflsjdflks" instead of "site.com/file.mp3". And no, removing that extra lkjdflsjdflks doesn't do anything. There are similar problems posted here in the forums but all the solutions given didn't solve the problem. I've already set media.directshow.enabled, went to Applications and set all mp3 format sound files to "save file". Even restarted my pc. I installed chrome and christ, the file downloaded with a single click (as it should always have been). There's got to be fix for this, I'm not switching to chrome as I've settle with firefox for a long time now, mind you. Also Third party addons is a big no.