Flash CS3 Keyboard Shortcut doesn't work

I'm sorry, I meant to post this under "Design and Graphics". I will repost it there.

I am running Flash CS3 on a 24" Aluminum iMac, 3.06Ghz, Leopard 10.5.8. The keyboard shorcut to insert a keyframe (F6) does not work. I have swapped out keyboards, tried to make a custom set of shortcuts in Flash, and I have already gone into Apple System Prefs and checked the box in the keyboard preferences that lets me use the F-Keys as standard F-Keys. I have tried pressing "fn + F6" and that doesn't work. I'm at a complete loss. I can use F5 and F7, but not F6. I have thrown out my Flash prefs and tried reinstalling it too, and nothing fixes it. Any clues? Couldn't find a fix via Google that worked for me. Thanks!