I have a customer with a Toshiba R840 with built-in web cam.
When they try to use the webcam, all they see is a static picture that is not one of theirs. This happens in all apps that would use the camera. When the web cam is in use, the red indicator works and the sound records. Any video recording shows that same static picture but the sound is fine,
I have deleted the drivers and reinstalled etc. and the driver reports that the device is working correctly.