Apple Final Cut Express HD - Manual (Page 277)

Chapter 21 The Fundamentals of Adding Clips to a Sequence 277
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Video and audio clip items can be linked or unlinked at any time. For more information,
see Chapter 29, “
Linking and Editing Video and Audio in Sync ,” on page 397.
Video clip item on V1
Audio clip items on
A1 and A2
...the audio clip items
move as well because
they are linked.
When you move a video
clip item to a new
track...
The video clip item is
now on V2.
Linked audio clip items
are on A3 and A4.