Apple Final Cut Pro 7 - Manual (Page 616)

3 Set up a split edit in the Canvas or Timeline at the place where you want your source clip
to appear.
Split edit with audio
preceding video
4 Drag the clip in the Viewer to the Overwrite section of the Edit Overlay in the Canvas.
The resulting edit looks like this:
Audio precedes the
video and begins at
the split audio In point.
Video begins at the
split video In point.
616 Chapter 41 Split Edits