Golden Gate 27.0.1 causing camera failure and persistent automatic reboot?

The fact that both problems appeared after updating to macOS 27.0.1 is certainly worth noting, but it does not by itself show that the update caused them. 

Apple’s published information for 27.0.1 does not identify a built-in-camera or automatic-restart problem. Apple’s macOS 27 update information

For the camera, start with System Settings >> Privacy & Security >> Camera and make sure the apps you are testing have permission to use it. 

If you use Screen Time, also check its camera restrictions. Apple includes both checks in its camera troubleshooting guidance. Apple’s camera troubleshooting guide

Then try the built-in camera in Photo Booth and another camera-using app. If you get the same black image in both, the problem is less likely to be specific to one application.

The next useful test is Safe Mode. 

On your Apple-silicon MacBook Air, shut it down, hold the power button until the startup options appear, select your startup disk, hold Shift, and choose Continue in Safe Mode. 

Apple says Safe Mode can help determine whether a problem is related to software that loads during startup.

Test the camera again. 

If it works in Safe Mode but not after a normal startup, that gives you a useful direction for further troubleshooting. 

If it remains black, Safe Mode does not by itself identify the cause.

If it still fails, testing the camera from a new macOS user account is another useful check. 

If it works there, the problem may be confined to your existing account; if it fails there too, that makes an account-specific problem less likely.

For the other problem, disconnect your external devices, hubs, drives, displays, printers, and other USB or Thunderbolt devices. and see whether the behaviour continues. 

Apple recommends removing peripherals when investigating unexpected restarts. Apple’s unexpected-restart guide

It is also important to establish exactly what the Mac is doing. I

f you choose Apple menu >> Shut Down, the Mac completely powers off, and then starts again by itself, that is an automatic power-on after shutdown rather than simply an unexpected restart. 

If instead it restarts while you are using it, check Console for a recent panic or shutdown-related report, if one is present.

Also check System Settings >> General >> Software Update for a newer macOS release. 

If one is available, installing it may be appropriate, although that does not mean it will necessarily resolve either problem.

Since you have already reinstalled macOS and run Disk Utility, 

I would not repeat either one for now. 

If the camera continues to fail in multiple apps, Safe Mode, and another user account, or the Mac continues to start again with peripherals disconnected, those results, along with your Apple Diagnostics information,would be useful when contacting Apple Support or an Apple Authorized Service Provider. Apple recommends service when the built-in camera remains unavailable after its troubleshooting steps.

Have the computer evaluated by the Professionals who have the Special Hardware Software and Expertise to diagnose the issue and offer possible solutions

Make an Appointment at the Apple Genius Bar or call 1 800 MyApple and have them evaluate the computer

Other location Call Centres 

 Contact Apple for support and service

Certain misconceptions persist regarding the respective responsibilities of Apple and third-party manufacturers when devices, applications, extensions, services, or accessories do not function as expected.

Apple is responsible for addressing issues with its own hardware, software, operating systems, and services. 

However, compatibility and functionality issues involving third-party products may require investigation by their respective manufacturers, particularly following an operating system update.

Third-party manufacturers are responsible for ensuring that their products are compatible with the versions of macOS they support. 

Apple’s guidance on this distinction is available here:

How to contact an app developer - Apple Support (CA)

I have tried all of those suggestions and the two issues remain.

For the camera, a safe mode start and subsequent diagnosis shows the camera failed the Frame Rate Test, but otherwise passed. There is also a noticeable processing lag on anything related to the camera, such as stopping/starting the camera in an application or quitting that application. No other computer functions are experiencing this lag, only camera-related actions.

As for the automatic shutdown, in 25 years of owning Macs, I've never experienced this inability to completely shut down a machine. Even with the lid closed and the Mac shut down, the power adapter light indicator cycles from off to orange to green and then the computer starts up on its own.

Again, none of this was happening before the MacOS 27 update, although I agree the correlation may not be causation.

I have a Genius Bar appointment to get this addressed.

My Logi USB camera has also stopped working since the Golden Gate update. It's old, so I bought a newer one, but it doesn't work either. I also tried the old one on my wife's Air, which isn't updated yet, and it works fine there. I'm not going to do everything your testing department should have done to sort it out. I expect you to fix it ASAP. We bought working systems, not test beds. Get it right.

PilotKJL wrote:

I have a Genius Bar appointment to get this addressed.

Yes that is your best course of action at this time