Edit: After half day, my wife’s Mac started having the same problem. I have then applied the solution that I found in the Apple
How To Watch The Live iPad 3 Video Stream On Your iPhone , iPod and iPad –
As you may know that Apple are having an event today at 6pm GMT which means a lot of people will be at work or school so we have made sure that you can watch or listen while in class. Below we have included a link which will allow you to directly watch the live video stream of the iPad 3 event.
Watch on iDevice : goo.gl/WtpZv
You can also download the UStream App and search MacReviews