My new MacBook Pro works nearly perfectly fine, and Safari works well, but YouTube videos are not working correctly. When I attempt to view a video on YouTube, the screen remains black, and the loading symbol appears in the middle, but the video never actually loads. However, the videos work when they are either embedded on another site or if I am viewing them directly from a member's channel. I was told on Yahoo Answers to check my download speed, and they said it should be at least 5 MBps, but I had over 16 MBps, so that can't be the problem. The YouTube videos also work on Google Chrome, but not Safari. Please help?