before you fry your machine with some malicious program, you can also try to pull the MP4 from youtube (in the videos settings when logged in) and then render only the audio with a program like Premiere Pro or even Blender (free, but a little weird for this task)
-- zuggamasta
I never realised you could do that, I did find a website that lets you paste in the video link to YT and then spits out an Mp3.
Enjoy your spare HP, don't rush to fill every last space, this is not like filling sticker books. Resist the urge to 'complete' your rack, its never complete so just relax.