FCPX Basics - Audio
Audio
Volume:
Click the line across the audiowave in the clip and drag it up or down to change volume.
Detach:
Right click on the clip. Click ‘Detach Audio’. You can now move and edit the audio separately from the video.
Import:
In the middle grey block on the right side you can click the music button to select audio files. You can drag and drop audio files into the timeline from there.