Is it possible with HMTL 5/javascript to add a button which will allow you to turn off a music background track but leave the voice audio running (in my mind this could be achieved by having a separate mp3/ogg/wav uploaded with the video).
Thinking about accessibility - some people find background music distracting and a barrier to learning/engagement. While they can mute audio and use subtitles, it would be nice to give the option.