System unusable during streaming ?

[Pierre]

Hi,

Every time I stream some mkv, or avi file, my whole system comes to a standstill, the mouse skips like crazy, nothing does react, allthough Task manager shows only 10% of CPU is being used ?

Please, what do i do wrong ?

I use XP SP3, Core2 Duo CPU, 4GB memory, and the standard Mencoder for streaming.

Please can someone help me ?