SDL-1.2.7 synchronizes on some windows box but fails on others. Why?

Hi,

I use mpeg4ip-1.2 (which uses sdl 1.2.7) to play .3gp file. It synchronizes on some windows box (e.g. IBM thinkpad T41) but fails on others(e.g. Dell Inspiron 5150). Why? Because mpeg4ip does not support windows, I ask for help here. Does anyone has similar experience or problem? Is the SDL synchronization feature hardware depended? How to fix it?\

Looking forward to your reply!

Best Regards,
Xie Bo