I'm using an iSight firewire cam on a Mac Powerbook G4, running the latest version of Tiger. When I start up the software, I have no problems viewing on my iPhone. But after anywhere from a few minutes to an hour, the software on the computer just quits. No error messages, nothing. I then get the error message that says no sources can be found. I've tried to look up other information in the other forum posts but I'm stumped. I turned off all screensavers and set my computer to never go to sleep, hoping it would help but it doesn't seem to matter. Please help!