Video is lagging/choppy on Final Cut Pro playback but audio is perfect

Theres not quite enough info here to diagnose the issue. Did the issue start when you copied the info to a different drive? Typically you want the media on one drive and the application on another.

Maybe drive speed, maybe ram, I'm not sure what the FCP requirements are but check here:

http://www.apple.com/final-cut-pro/specs/

What John said. More details would enable others to help.

If you click the Apple logo > About This Mac, how is the MBP model described?

What format are the clips that you're using in your project? Do you know what camera shot them?

Please post a screen shot of your project timeline. That may provide a clue as to why the only part of the video is exporting

Thanks.

Russ

WhosCristinaa wrote:

Also, I imported the original footage to an external hard drive so my computer would have more space. Not sure if that makes a difference but I figured I should add that just incase.

Can you tell us the type of external (USB 2/3, firewire etc.) you copied to and how it is formatted please?

Al

You probably have either a corrupt clip or a corrupt render file somewhere in your project. Start by deleting render files. Select your project, and go File->Delete Project Generated Files... and chose to delete All render files. See if it exports fully.

Your connection to the external drive is most likely USB2, since your mac does not have USB3 ports. The fastest connection you have available is FW800, but even that is slow by today's standards. I believe that this will limit what you can achieve. But do note while this will affect playback, it should not affect what you export - hence my suggestion above.

Thank you for posting that additional info.

If after following Luis' render file suggestion, your export is still partial, please post another screenshot of your timeline. But before you take the screen shot, please zoom out (Shift-Z) to reveal the full timeline.

Russ