ferrari Said:
"I have an M1 MacBook pro, and when I started the MacBook for zoom, it grabbed the camera on my iPhone and the builtin camera seems to be disconnected in the boot up process. The green light flashes once or twice."
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Reinstall the macOS:
Seems drivers have gone missing, somehow. So, reinstall the macOS. If you reinstall the macOS, nothing would be deleted. All intended, original files and ppps that came on your macOS would be reinstalled. It’s all about keeping your system files intact.
1. First, Create a Time Machine backup:
Important: Create a Time Machine backup of your Mac, so that you can have something to restore your Mac from, should anything go wrong with the reinstall.
2. Reinstall the macOS:
Go Here: How to Reinstall macOS - Apple Support