Apple Final Cut Pro 7 - Manual (Page 130)

130 Chapter 6 Working with Audio
Edit a sound using keyframes:
Position the playhead at the beginning of a sound, such as a click or pop, that you want
1
to eliminate. For now, just pick the beginning of the second whistle in Audio Clip 1.
Position the playhead
at the beginning
of the sound.
Click the Level Keyframe button to add a keyframe to the clip at the position of 2
the playhead.