Audio synchronization in AVI

Hello, when I make a videocd, audio and video are well synchronizated, but when I make an avi, DivX or XviD, mp3 CBR or VBR, audio only is synchronizated with video if I play the movie from the begining without jumping to a forward point with the slider bar of the player, if I jump to a forward point, then audio doesn’t have any synchronization with video. Somebody can help me?
Sorry my english.

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