I have received my 2nd replacement iSight from Apple support today. See http://forums.macrumors.com/showthread.php?t=90298 for original fault. Anyway, the 2nd replacement does similar to the first replacement: After a couple of minutes idling in iChat (to test) the image freezes, if I force quit iChat and re-launch I'm told the camera is in use by another application. This can't be another faulty replacement surly. I'm using OS X 10.3.6 on my PowerMac dual 1.25 GHz (FW800) I tested the 1st replacement under the following conditions: Different firewire cable. Only firewire device connected. On iMac G5. On 10.3.5 booted from my firewire drive. Please HELP !