[metafunctor]

These are great videos, and the content itself is, in my opinion, pretty good.

It seems to me these have been narrated by a professional. The narrator's voice is pleasant and pronunciation clear, but it seems he doesn't really know what he's talking about.

I would prefer the voice of an actual subject matter expert; they would be able to better convey which parts are actually key concepts, and which parts are just intermediary math. Now it feels like everything is equally important, when it's clearly just some intermediary math to get you to the actually interesting part that follows.

I agree that the continuous music is distracting. The quick fix is to fade the music away for the content. It would be fine to leave in for the beginning, end, and transitions.