busy timeout[0], (60s): 'AppleAPFSMediaBSDClient'

You nailed it! That's why it was difficult to identify the cause...for me it happened after sleep mode sometimes immediately and other times minutes later after "waking" during different tasks. Thanks for sending links to this thread to crash report.

I'm now having trouble with Safari bookmarking....that crashes every time I try to "bookmark" a site. it.

Not related to this Media Client issue, , but related somehow to update.

Thanks AZ Coder 1959..for the Safari test.

There's some chatter on the net by other users with the same issue but I did pursue any fixes.

Then... suddenly tonight the Safari bookmark glitch suddenly stopped on my end. Gremlins?

Anyhoo, I hope11.6.3 comes our way before the new moon.

Thanks for sharing that workaround, it's been helpful! It's sad that we need to take a few extra steps to make sure our computers don't crash and burn, but this is good to know.

On another note, macOS 11.6.3 is out now. Haven't updated yet because I'm in the middle of work, so has anyone else updated and tested whether the bug is fixed?

Somehow diskutil commands don't work the same way when run inside a Quick Action created in Automator.

For example, the command:

diskutil unmountDisk /dev/disk4

ran in the Terminal does what it is supposed to do, but the drive won't unmount when I put the same command in the Utilities/Run Shell Script action.

Having the same problem: a crash shortly after:

1. External TimeMachine disk disconnect
2. Close lid
3. Open lid

This happens on a MacBook Pro M1 (2021). The crash was easy to reproduce and still happening in Big Sur 11.6.5.

DiskUtility at MacOS BigSur 11.6.5 does not let us eject the physical disk: "it was not possible to eject "<disk name>" because it is being used". This disk has 2 logical drives in it, and they are not being used at all. Then, I ejected in DiskUtility one of the drives, the other I couldn't. I was forced to go to Finder and force eject the remaining drive, and both were ejected. However the LED is still blinking at the external disk and the DiskUtility continues to see the disk. If I try to eject the physical device (the highest level as shown above), there comes again the same message, saying that it is not possible to eject the disk because it is being used.

It's certainly frustrating. If the reports are correct, this is not an issue in Monterey, which begs the question why can't the fix be ported over to Big Sur?

I have a couple of guesses.

One is technical (a fundamental change to the OS needs to be changed, which can't be done without breaking a dozen other things). The other is a workload issue (they have other priority fixes in the queue and no one in management has deemed this to be very important).

I hope the Big Sur fix is sooner than later!

For various reasons I am not able to upgrade to OS Monterrey yet but do wonder if the

problem will be there as well. Anybody know?

Yes, exactly my problem, too. It's a bug in 11.6.2 for sure. My machine is brand new and had been performing optimally until the OS update.

I don't use Safari that often, but I just tested it and haven't been able to reproduce the error you're seeing.

To add further proof to your theory, I ran a TM backup and rebooted after ejecting the external drive. After it booted, I closed the lid. An hour later, I woke up the laptop again and it's fine.

Gremlins, indeed. Seems like they have a few live ones running around. 😆

Quite helpful! Thanks for the tip.

I tested your workaround and confirm it works for me, too. Thanks, again.