Apple Final Cut Pro 7 - Manual (Page 1885)

The audio is not in sync with the video, or you’re experiencing dropped frames in your
video
Many audio sync issues stem from dropped frames on capture or output. Nearly all
dropped frames are caused by either incorrectly configured hardware or incorrect
preference settings. The leading causes of dropped frames are the following:
• If you’re using external speakers connected to a camcorder, deck, or third-party capture
card, and external video is set to All Frames, the video displayed on your computer’s
monitor (from the Viewer or Canvas) will not be in sync with the audio. The audio will
instead be in sync with the video that is displayed on the NTSC or PAL monitor that’s
connected to the same output device.
• If your clip or sequence is zoomed while open in the Viewer or displayed in the Canvas,
frames can be dropped. Choose Fit to Window from the View pop-up menu in the
Canvas or Viewer.
• The computer display is set to a low refresh rate. The refresh rate in the Displays pane
of System Preferences should always be set to 75 hertz (Hz) or greater. (This is not
applicable to flat-panel displays.)
• The Canvas and Viewer windows are overlapped by other windows; they should not
be.
• If more audio tracks are specified to be mixed in real time than your computer can
handle, frames can be dropped. Reducing the number of tracks in the Real-time Audio
Mixing field in the General tab of the User Preferences window will result in your having
to render your sequence, but will result in improved playback.
• Incorrect versions of Mac OS X and QuickTime can be another cause of dropped frames.
Check the Final Cut Pro website for the version of system software you should use.
• The hard disk drive you’re capturing to is inadequate for capturing video. This could
be caused by slow hard drives, incompatible drivers, or configuration issues. For more
information, see
“Determining Your Hard Disk Storage Options.”
• Another source of dropped frames on capture or playback may be fragmented hard
disks. In general, it’s preferable to capture to disks that are specifically reserved for
video. To avoid fragmentation, you should avoid filling up your disks with numerous
files unrelated to the projects you’re working on.
1885 Appendix A Solving Problems