Solution One: Delete Preferences And Restart
You can delete the preferences file and restart the computer to eliminate this behavior when it occurs. Afterward, Final Cut Pro will function normally.
Solution Two: Multiple Users
A better solution is to use the Multiple Users control panel in Mac OS 9 to create multiple users, allowing you to quickly and easily switch between settings without having to restart the computer or discard the preferences file. This may be done even after the Targa Card and Final Cut Pro have been installed.
Assuming you chose the Targa settings when installing Final Cut Pro:
1. Make sure that Final Cut Pro is not currently running.
2. Open the Multiple Users control panel. Create two new users, one named "DV" and one named "Targa." Be sure to create Normal users and not Limited users, and give both equal read/write privileges. For more information on creating new users, please see article 31171: "Mac OS 9: Set-up and Management of The Multiple Users Control Panel"
3. From the Finder, open the Special menu and choose Log Out.
4. Log in as the user named "DV."
5. Open Final Cut Pro and change the capture settings to DV.
6. Quit Final Cut Pro.
Each user created in the Multiple Users control panel possesses its own set of preferences for each application. When you wish to capture DV material, simply quit Final Cut Pro, open the Special menu in the Finder and choose Log Out, log back in as the "DV" user, and open Final Cut Pro again. When you wish to capture with the Targa card, simply log out and log in as the "Targa" user. Each set of preferences is kept separate from the other, so there will be no conflict.