Yitbird,
Sorry about the trouble.
I can't duplicate the problem. The songs play fine for me.
If you still have problems, try another browser and/or computer real quick just to make sure it isn't a local problem. Also, try switching from high resolution to low, or low to medium, just make sure it is all videos on all browser on all computers available to you.
Then, if you still have trouble, create a support ticket and we'll help you troubleshoot further.
http://www.guitartricks.com/contact.php
Jon