It could be.
Because these video apparently didn't come direclty from a camcorder and you've no idea what their specs are, you should open the video in G Spot.
Post a screen shot of the G Spot report so we can see the video clip's specs and we'll better be able to advise you.
Welcome to the forum.
Several users have experienced OOS (Out Of Sync) issues when using the Apple H.264 CODEC for Export/Share. In many cases, going with either the MainConcept H.264 CODEC, or the Lead H.264 CODEC, has solved many of their problems. I have not been able to gather enoung input to determeine if one of those other two H.264 CODEC's is better.
Apple's is free, and part of the Apple QT Player installation, so that is the one that most users have. The other two are commercial CODEC's, and must be purchased.
If you find that one of those is better for you, please let us know.
What if I converted the video into a different format first, edit the videos in the different format, and then convert back to the Apple Codec? Would that work?
It is possible that things would improve, but from my reading (I so very seldom use H.264, so do not have a lot of personal experience with issues), it seems that most of the OOS is introduced IN the Apple H.264 Encoding. Please Note: those observations come from reading a ton of posts on similar issues, where others have experienced the OOS on Export/Share. I have, and use the MainConcept H.264, though sparingly, as I just do not need H.264 output that much.
- What project preset are you using?
- If you create a project for each clip is the audio/video correctly matched? If so, export from those projects to a common format output file, and combine them in a new project.
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