Quicktime 7.6 update was installed on our 10.4.11 OS. In final cut when we go to play back video there is such a huge lag that the video is like a freeze frame. We get audio out. Tried changing playback settings to 1/4 frame rate-low quality.. Helped a tiny bit. We wiped out quicktime and installed quicktime 7.5.5 (Version FCP requires to run). No Bueno... Still has serious lag issues... HDD has 80 gigs free... Tried booting up projects from external drives w/ scratch disks set to external drive. No good. Has 5 gig ram.. G5 kona card.... I dont know what else to try stuckkkkkkkk! HELLLPPPP!!!