subtitle - timing error and no effect

[Eahawk]

hi guys.
few days ago i made a karaoke script in ssa, and i preview it in mpc.
Everything was perfect the timing and even the effect i made.
but now when play it again , the timing is too fast, the effect (like fade out, scale) doesn't come out, and even the karaoke doesnt work also. ( what i rembereed that before i play the sub & the mpg file, i 've istalled a codec . But although i remove it, the subs still doesn't come out right). I've tried unistall and re-install my vobsub too.
Can u help me, plss

[Cyberman]

Are you using DirectVobSub to display the subtitles?

If so, try to disable "pre-buffer subpictures" in the Misc section.
When enabled, that will screw up the karaoke effect(half the line is highlighted, half the line isn´t).

At least it´s been that way in the file(s) I have.