Audio Out of Sync on Original Files ??

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Seth Stark

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  • Joined: Fri Sep 08, 2017 2:47 pm

Audio Out of Sync on Original Files ??

PostThu Apr 12, 2018 4:25 pm

I just did a shoot with my BMUMP4.6K and the audio is not in sync with the video. I am playing the actual files that came off the card, that I transferred to a hard drive.

Footage from all my previous shoots is fine.

I've confirmed the issue is not related to the hard drive - the problem is with the original files from the camera.

Does anyone have any idea why this would happen?
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Thomas Hennessy

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Re: Audio Out of Sync on Original Files ??

PostThu Apr 12, 2018 5:01 pm

Check your frame rates. It is possible to shoot with a project frame rate of 24fps and then off-speed recording get turned on at 23.976 or vice versa which will result in slightly out of sync audio.

Are all your shots out of sync? About how long is each take?
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Robert Niessner

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Re: Audio Out of Sync on Original Files ??

PostFri Apr 13, 2018 6:53 am

In addition to what Thomas said, this will even happen when you have off-speed recording activated and record to 25/25 or 24/24 because in off-speed mode the camera cannot keep audio in total sync.
So yeah, check your settings, in normal mode the camera locks the audio in sync.
Robert Niessner
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Seth Stark

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Re: Audio Out of Sync on Original Files ??

PostTue Apr 17, 2018 12:04 pm

The clips range from 5-20 minutes each. The audio starts out in-sync but is way off by the end.

I will check the camera settings going forward.

For now, is the only way to fix this footage to adjust the speed of the video?

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