audio sink

Could somebody help me with a small problem i have? I have downloaded a couple of films with lime wire basic, burnt them onto disc and played them on my dvd quality great, but after about 10min into the film the audio seems to go out of sync.

i.e speech follows after mouth movement.

H.E.L.P
Lee

Easiest to 1st try them on another computer that maybe has the right codecs installed. If it's the same than I bet it's just a badly done rip.
Might be things you can do to fix it but I can't remember the details right now. Sorry. I think I have seen other people writing about this same thing here in these forums.