I am suing safari browser. It was found two days, when watching youtube always suggest that Flash needs to be upgraded, then refresh the page can be viewed correctly. If i click on a page with new video no problem, but simply open a new tab or window will prompt you to upgrade Flash. So to upgrade the official Flash result, the problem still exists. I also tried the firefox and chrome, are all normal. I do not know any solution for it? Thanks in advance.