Click the OK button and then exit out of Avidemux. Give Avidemux a few moments to do its thing.Leave the video type as mkv and then click the Save button. Give the video a new/different name so that you don’t overwrite the original, which you can delete later once you’re sure the new video is perfect.Once you’re happy with the result, select File and then Save.Use the Play button to determine if the video is now in sync with the audio and keep adjusting with the up and down arrows until it is.That will ‘delay’ the audio, allowing the video to ‘catch up’. That means if the people in the video are talking and you can hear them before their lips move, you’ll want to use the up arrow. Use the “up arrow” in the Audio Output section to increase the number of milliseconds if the audio is ahead of the video.With the video paused, place a check in the box labelled Shift, which can be found in the Audio Output section.Use the “timeline slider” (see screenshot below) to move the video forward a bit. After a few moments the video will open up in Avidemux.Navigate to the video file that’s out of sync, select it and then click Open.Once you’ve downloaded and installed Avidemux, open it.
Note: the screenshots used below are from a Mac, but the steps and screens are nearly identical if you’re using Windows or Linux and you should have no trouble at all following along. It’s cross-platform which means it’s available for Windows, macOS and Linux.
To permanently fix out of sync audio and video, you’ll need to download an open source (free) video editor, Avidemux. Permanently Fix Out of Sync Audio and Video Let the video play while you’re making the adjustments – but note that it’ll take a second or three for the change to take place each time you adjust the sync timing. In both instances, when you use the up and down arrows it will adjust your audio by 1/10th of a second per click. So in reverse, if the audio is behind the video you’ll want to use the “down arrow”. Use the “up arrow” if the audio is ahead of the video.Locate the section titled Audio/Video – within that window there’s a ‘timer’ with “up and down arrows” to adjust the timing of the audio.Open the video with the out of sync audio in VLC and then select Tools -> Track Synchronization (Mac users: select Window -> Track Synchronization).Note: this will work for all video formats, not just mkv/mp4/avi – they’re just common formats (and the 3 that I’ve found most often have sync issues). If you aren’t using VLC yet, head over to their download page and give it an install. The quick solution is to use the amazing (and free) media player – VLC, and its easy to use built in audio delay/forward feature. Temporarily Fix Out of Sync Audio and Video There are two ways to fix out of sync audio and video – one is temporary and quick, the other is permanent and a bit more involved, although still quite easy.
This step by step guide will show you how to fix out of sync audio and video in a video file.