Capture the streaming but when playing the frame is too slow

[JFreak]

I have just bought Replay Media Catcher 4. I downloaded the streaming from vtc.com. It succeeded but when I played it. The picture was so jerky and slow and frame was not smooth.

http://www.vtc.com/products/CompTIA-Aplus-2009-Edition-Practical-Application-Exam-220-702-Tutorials.htm

and tried "the Page file" under The Windows OS.

What should I do?