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Editing some of the more
highly compressed video formats has the risk of OOS. There's no single cure for it. Some will split the audio and move it trying to re-sync, while others will speed up the audio slightly.
With the older versions of VS, editing MPEG-2 had this OOS problem, so we recommended to not edit MPEG-2. VS Pro X2 seems to have improved, since it is capable of editing very highly compressed video such as AVCHD.
Is your OOS occurring in the final rendered video/dvd, or just while previewing within VS? If the latter I would not be too concerned as it will always be a rough idea of what your finished product will be. VS throws everything together
on-the-fly, resulting in a jumpy, stuttering, previews.
When you create your video file (Share>Create Video, or Share Create Disc), are you checking the option,
Do not convert Compliant MPEG.., and are you choosing to use
Smart Render?