#biggest offenders of 'needing to be uploaded as an mp4':

[doyoulikethis-videogame-song]

How do you know a song needs to be uploaded in mp4?

Some songs have some weird DRM or just won't let me upload them as MP3s for whatever reason (I don't know until I try to upload them as an MP3 though, haha).

A lovely follower of this blog helped me out a long ago with a noise filter that bypassed it but it ended up being less time consuming to just convert them to MP4, so I made a silly image in mspaint and that was that.