I've got an iMac 27" paired with a Thunderbolt 27" display that's rotated to portrait mode. Both of them have integrated webcams. Some applications are screwy and inconsistent about letting me pick which webcam to use.
I always want to use the webcam on the iMac and never the one on the Thunderbolt display, especially as it's rotated so the webcam image is not only off-center, but 90 degrees in the wrong direction.
Is there any way (defaults setting or something) for me to disable the webcam on the thunderbolt display, but still let the webcam on my iMac to function?