I don't do much video editing but I have done this multicam stuff a bunch of times and it's only recently I've had this problem.
All I've done is:
- Open Final Cut,
- Create New Project,
- Dragged my videos into the clip section,
- Highlighted three clips and selected 'Create Multicam Clip'.
- Dragged the Multicam Clip into the Timeline.
The videos are three angles of a band's gig taken from an SD card, from two GoPros and a Zoom Q3HD.
When I play the project, the multicam clips are sped up.
When I open up the multicam so I can view all the angles in the timeline, the clips play at normal speed.