Back in the 90's, I did some video work and I found the better video editors used markers for synchronization. But some of the cheap stuff didn't. You could easily get out of sync on software that was bundled with PC image grabbers, but something like the NewTek Video Toaster had much more capability. Check the DigitalAudio and DigitalVideo forums because they discuss issues just like these. Those forums are still small, but I saw a post or two there about stuff like this.

Wayne