If you’re getting WEBM audio files instead of MP4 from YouTube or any other site. (webm can only be played in a browser) , disable your browser’s WEBM audio support, then YouTube or media site will send the audio in MPEG4 format.
- Type “about:config” in the address bar
- press
Enter
, click through any warning message and search for “webm”. - Find and double-click
media.mediasource.webm.audio.enabled
. - Its value will change to
false
and you’re set.
Enjoy!