I have a pretty strange problem with YouTube: when I just go on YouTube and watch any video through Firefox, Chrome or Chromium (both with Flash and HTML5 players), it works perfectly.
BUT! When I log into my Google account and try watching any video while being logged in, it doesn’t play; it just shows me the “rolling wheel” icon on the screen (as if is loading).
I've done this test on a completely fresh system, without any changes, and on a system with some drivers installed. I had the same result on absolutely all distributions of Linux that I've tried (Ubuntu 10.04 LTS, 12.04 LTS, 13.04, Mint, Fedora, OpenSuse).
So, where could be the problem?
Best Answer
It might be because now that Youtube/Google knows who you are, they are trying to customize the pre-roll advertising to you
So, as a "normal" anonymous person, just by luck it turns out the advertising loads fine (even if it's just bottom of the video ads)
THEN, you log in, and through bad luck the CDN that is now serving your ads (or tracking your specific account through cookies), or any number of other servers that is used, is taking a long time to respond - and it causes the video to hang.
If this is going on for weeks or months then that is a different story - but if it's just a day or two, that's probably what it is. I have had that happen to me as well, and it didn't even matter if I went to different locations/wifi networks.