ArisB wrote: ... Why would this happen?
Because either:
(1) you (or someone else) have added software that turns the camera on and off automatically, or
(2) something is wrong with your Mac's hardware or software.
If you did not do the first and have given others access to your Mac, you can eliminate (1).
Here is how I would work the second possibility: Uninstall (follow Skype's uninstall instructions) Skype. Then restart Mac, use Disk Utility to repair permissions, and then test your camera again. Follow the suggestions inApple's http://support.apple.com/kb/HT2090 article.
If the camera works correctly now, reinstall the latest Skype that is compatible with your Mac. If the problem returns when you install Skype and goes away whenever you uninstall it, Skype must be causing a conflict that results in your camera's unexpected behavior. Search or post in Skype's dedicated support pages for help for this Skype-specific problem.
If the problem continues even when Skype is properly uninstalled, post back with as much info as you can provide on the latest behavior. Confirm that you have used the proper SMC/PMU reset from the Troubleshooting article, and tell us which (if any) apps and user accounts work properly and which do not. We will offer more specific suggestions based on the details in your reply.
Message was edited by: EZ Jim
Mac OSX 10.7.3