Youtube not Working on Safari

Since yesterday, Youtube hasn't been working for me when I use Safari.

If I click on a video, the comments and everything will load, but the spot where the video itself should be playing is just a black screen. Researching this problem, it seems that it's usually a firefox issue, but I'm having it on Safari.

Youtube is working on Firefox, so it's not just Youtube being down or something. Also, I can't see embedded videos from Youtube on forums or anything.

Things I've tried and have failed:
- Resetting Safari (clearing cookies/cache)
- Logging out of Youtube
- Resetting my computer
- Turning off my ad blocker
- Changing my I.P. (probably stupid, but just in case I got super banned from youtube somehow)

Anyone else having this problem?

Any suggestions to fix it?