I had the same problem. I found out, "Well this worked for me" that the media_play only played media of a certain resolution and also if you didn't lock the FPS to around 60 they where choppy.
Windows XP SP3 Intel Dual Core CPU: E5200 @ 2.5GHz 4.00GB DDR3 Ram ASUS P5G41T-M LX PCIE x16 GeForce GTS 450 1Gb SB Audigy 4 Spyware Doctor with AntiVirus
