So, it seems like I am the only one who has this issue, but it's quite bothering me, because it's not really practical to have my second laptop always on next to my mac when I want to use youtube. Everytime I play any video, there seems to be no problem, however, somewhere in the middle, it starts loading although the loading bar was far away from the actual time. When this happens, I have to reload the whole page because the dot will move to the beginning of the video and it won't load even if I waited for an hour. It happens in all browsers, but only on my mac. The Windows laptop plays it well. I don't use HTML 5 YouTube and even if I do, it doesn't help. I have the latest flash and tried to reinstall lots of times. Anybody knows where is the problem?