Final Cut Pro X: Sync audio and video automatically
Final Cut Pro can automatically analyze and sync the audio and video clips in your project.
For example, if you select two video clips and three audio clips from different sources that were all recorded during the same take, Final Cut Pro automatically analyzes and syncs the clips together into a new clip in the Browser.
Final Cut Pro analyzes the clips for sync points such as markers you’ve added, timecode, file creation date, and audio content. If no sync points can be found, the clips are synced at their respective starting points.
Choose Clip > Synchronize Clips (or press Command-Option-G).
Synced clips are labeled “Synchronized Clip” in the Browser. The original clips are not affected.
If your synchronized clip contains audio channels that aren’t being used, you can turn them off. See Configure audio channels.