MP4 playback?

[Risim]

I followed instructions here on older post and downloaded k-lite codec with and update but some mp4 play great but some are not in sync(audio/video are not exact). Any ideas, driving me crazy

[coffee]

In my experience most of this issues comes in if you use a different codec pack in any part of the proses from downloading a track, converting to mp4 or editing the song.
You can also try installing K-Lite with the "lots of stuff" feature, when finished installing, install K-Lite again by selecting the "lots of stuff" option again but this time tick the 2 Divx/Xvid boxes near the top of the list and the one near the bottum of the list.