It worked for me with Firefox and Windows 7 64. Obviously this isn't helping your problem telling you that it's working for us, but I really don't have a solution, especially since the other clips are working for you.
Computer type PC/Desktop System Manufacturer/Model Number Self build OS Windows 7 Home Premium CPU Intel Core i5 3550 Motherboard ASUS P8Z77-V LX (LGA1155) Memory Corsair Vengeance DDR3 16GB Graphics Card Asus Radeon HD 6670 Monitor(s) Displays Hanns-G 23.6", Acer 17" Screen Resolution 1920x1080, 1440x900
Using the same pc I just tried to watch the ABC video on a Ubuntu installation in a virtual machine on my C Drive. It played as it should have. This suggests to me that the problem is strictly in my Windows installation.