I got my new Mac Pro yesterday, set it up, and everything ran smoothly. Today I was watching an episode of Lost on iTunes and the entire system froze up on me. The video and sound both froze and I was forced to preform a hard shut down and restart. I started the video again and sure enough it froze after about 2 minutes. Does anyone have any idea what is causing this. I watched a couple shows earlier in the day and everything went fine. BTW my Mac Pro is a Quad 2.93 with the 4870. Thanks for any advice.