This is about the first time I’ve read of FCP3 running in Tiger, so don’t know if indeed that is the problem. However an upgrade to FCP 5 would more than likely fix you up.
You bought the pro version of QT 7 then? so you could export MPEG-2?
Might save some money though if you don’t need to do the upgrade… If you didn’t install Tiger as a clean install ( you just clicked “upgrade” from the tiger disk) you’ll likely have problems with FCP. So if you were to try a clean install you might clear things up (as in erase and install AFTER you’ve backed up all files you need to keep, or better yet, buy another internal drive to add to your mac and install tiger and FCP on that new drive, leaving the old intact so you can move files at your liesure, or add them with the tiger install automatically).
Jerry
Apple Certified Trainer
Author: “Jerry Hofmann on Final Cut Pro 4” Click here
Dual 2 gig G5, AJA Kona SD, AJA Kona 2, Huge Systems Array UL3D