Disable the webcam as input device.
Every time I disable it, it turns back on when I try to capture.
Must be one of the benefits of a MAC.
unplug the webcam?
disable or uninstall it from the device manager if it's built in?
I always assumed you could choose your source in the capture window (or given, somewhere inside settings), but I've never had the experience of having to. Look for relevant settings inside project settings, sequence settings, as well as program preferences.