How to sync video and audio? Desync is a frustrating, immersion-breaking problem that may build up as the video goes on. It may happen due to different causes. Depending on the cause, it may sometimes be fixed in the player, or you may have to resort to editing software. Whatever the case, this article should help you identify and solve the problem.
Adjusting audio delay in a video player for Mac is the simplest desync solution, that doesn’t require you to edit and re-render the video in any way. In Elmedia Player, this option can be found in Audio - Increase/Decrease Audio Delay. If you need to change the delay by a lot, we recommend that you use hotkeys. This makes the process easier and quicker. Note that this fix will only work if both tracks have the same duration. It won’t help if audio or video is sped up or damaged with missing parts.
2. Start playing the video.
3. If the sync audio and video aren’t aligned, or if audio needs to be slowed down, select Decrease Audio Delay. Delay option in the Audio menu (or use the ‘⇧⌘[‘ hotkey).
4. When the situation is opposite and the audio is behind the video, select ‘Increase Audio’ option in the Audio menu (or use the ‘⇧⌘]‘ hotkey).
Whenever you are adjusting the timing, the OSD message will be displayed in the top left corner of the player window. The message quickly disappears once you are done.
VLC has a sync option for audio. It’s easily accessible, and works both if the audio is too far ahead or lagging behind. Once again, this only works if the audio has the same length as the video. In other cases, you’ll need to edit it and adjust the track length.
1. Open a video in VLC.
2. Click Window - Track Synchronization.
3. Set "Audio track synchronization".
Remember that you can also set it to negative values. Useful if the audio is ahead of the video.
If you find yourself frequently rewatching a desynchronized video, or don’t have access to a player with an adjustable video delay, you can use an editing app. If done correctly, this will permanently synchronize your file. iMovie is a good choice, since it’s a stock that you can find on any Mac.
There are several possible reasons why a video might have bad sync.