Why does embedded video cause audio sync issues?

Greetings all,
   I have a question that is perhaps best answered by an Adobe developer or someone who knows the SWF file format and various audio/video standards fairly well. When one drags an FLV file into the library in flash authoring tool, a window appears. If you click "Embed FLV in SWF and play on timeline", an awful message appears, "WARNING: Embedded video is likely to cause audio synchronization issues...". My question is: why would there be any audio synchronization issue? Is this really just a bug/unimplemented feature? Or is there some fundamental shortcoming of current versions of the SWF file format that does not allow for the FLV audio/video signals to be properly encoded in the SWF file? Or is it that the flash player plays SWF and FLV data in fundamentally different ways and that even if the audio/video is perfected sync'd in the SWF file, the fact that it's a SWF file causes flash player to lose sync?
   I'm guessing only a Flash developer could answer this (and probably not just any Flash developer!), so if there are any out there, please spare some wisdom for a poor lost SWF surfer.
   Thanks!

Hi:
Welcome to discussions!
From what I am reading, you are trying to use the audio that was in the original video-right? By that, I mean, you haven't added a voice over or music-just using the speaker's voice on the tape.
If so, you might want to try using something like a Fade Out or Fade In instead of one of the transitions that add or subtract to the length of the video
[Quoted from iMovie Help]
Some transitions (for example, Cross Dissolve and Push) shorten your movie by a few seconds, depending on the speed of the transition. For example, if you add a transition with a speed of 2 seconds, iMovie overlaps 2 seconds from the first clip and 2 seconds from the second clip as it renders the transition. This shortens your movie by a total of 2 seconds.
The Overlap transition freezes the last frame of the clip on its left and superimposes it over the next clip. Fade In/Fade Out blackens the last frames of the clip on the left and the first frames of the following clip.
[End quote]
Or you could try extracting the audio from the movie so that you could edit it and sync it that way.
Sue

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mogreen wrote:
camcorder on 16bit, i am using a vhs player attacthed to camera then firewire to imac, ... the imovie project is perfect in everyway. Everything is pal. Yes i did export to QT within IM and this was also out of sync.
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you told us, video is 25fps, and audio is included 16bit (which is good...)
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so, please answer my audio Q from above: source, format, bitrate...?
and just for curiosity: how long is your project in total? hh:min:sec?
==edit==
pops into mind: in iM vers3, there was some 'bug', concerning PAL wrong audio and NTSC good audio ... wow < scratching bald head > .. try to contact some wiseguy with better memory..
Message was edited by: Karsten Schlüter

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http://support.apple.com/kb/TA25603?viewlocale=en_US
http://discussions.apple.com/thread.jspa?messageID=8113985
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