Apple is preparing a supplemental update for OS X 10.8.5 to address several issues with FaceTime HD cameras on the company's latest MacBook Air models



From MacRumors:

The update, which arrives as Build 12F42, has been seeded to Apple employees and should be making its way to a public release in the near future.The OS X v10.8.5 Supplemental Update is recommended for all users running OS X Mountain Lion v10.8.5.

  OS X 10.8.5 Supplemental Update Being Prepared to Address FaceTime Camera and Other Issues