.mkv frame rate lag and ReClock

[DarkFireBlade25]

when I run 48 khz mkv videos, the video always lags for some reason. I read that it is to do with the compatible frame rate on the computer so I downloaded ReClock to fix it. However, Reclock never runs when the video is playing even though I set it up to prompt me when it runs (and it does). Is there any thing for winamp to de-lag these kind of problems or is there a way to get ReClock to work?