Hi Joseph:
Even though your particular camera is not listed-this may help...and some Canon cameras do not work well when daisy-chained...
Macintosh: FireWire Issue With Some Canon Mini-DV Cameras
http://docs.info.apple.com/article.html?artnum=61603
I realize your camera is controlled by the mac, but there are alot of good hints here-be sure to read about the firewire issues...
iMovie: Cannot see or control camera
http://docs.info.apple.com/article.html?artnum=43000
Try deleting the imovie preference file. Locate a file named
com.apple.imovie3.plist and get rid of it. (It is still called iMovie 3 even if you have iMovie4)Then empty the trash, run a permissions repair with disk utility and restart. The files you need to delete are found in:
/Users/
YourName/Library/Preferences/com.apple.imovie3.plist
Come back if these do not help-
Sue