TK-949 said:
I asked, because I have the same problem as this guy here:
http://originaltrilogy.com/forum/topic.cfm/Matching-VHS-audio-to-a-DVD-video/topic/15348/
I want to sync the audio of the german Making of Star Wars VHS Tape to the BluRay version of the documentary. But it gets in and out of sync a lot, although it has the same length and fps (after a little conversion).
Ah! I see. I will admit I've never actually done this myself, and was speaking theoretically, but the link you sent does bring up an interesting set of questions.
Spaced Ranger says the following "(Only some?) capture cards sync audio to the video on-the-fly and don't always make a full accounting of "rounding errors" in it's sync-delays (both "+" and "-"). All other things being equal, this causes instances of drift that may or may not cancel out each other across the length of the stream. Editing can exacerbate these errors. This information (for mpeg, as best I know) is fully embedded in the audio stream (.MPA, .MP2)"
It could be errors in the VHS capture.