i’m thinking this might be somewhere between regional CDN issue, and the youtube API wanting to serve you ads, as @docteh mentionned. if you use any kind of VPNs maybe try changing servers, country, or disabling it. that might (or not) contribute to getting a connection going
i’ve also had issues with youtube, or even VRCDN after someone put a youtube link.
especially in certain world that uses custom video players assets (like ProTV Beta).
usually the best way to test; is to find a world with the vanilla udonsharp player and see if that works there. you’ll know then if it’s a world issue or a vrchat/provider issue.