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?

Here is a little manual to eject your external disk drive with "one-click":

Detect the drive you want to eject. Open Terminal, type "diskutil list" and press enter.

Choose the given device. In my case: /dev/disk4

Now create a new shell script file

touch eject

Edit this file

nano eject

Press the button control ^ + x and save the file

Make this file executable

chmod a+x eject

Now you can move this file to your Desktop with "Finder" and you can execute by double click on it :)

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.

I'm also having exactly the same issue with a MacBook Air (M1, 2020).

It also started happening after upgrading to macOS 11.6.2

It also occurs when awakening after having disconnected an APFS volume (used for Time Machine)

Updating to macOS 11.6.3 does not resolve the issue.

It is still an issue that is not fixed with OSX 11.6.4. As it tends to occur when opening MacBook Air (M1, 2020) after a period of sleep it may indeed be a problem with Time Machine, I will try to reproduce the issue by running a scheduled backup.

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.

Try this: after you eject the physical drive in DiskUtility (and the logical drives disappear from your desktop), close the DiskUtility completely. I had the same problem and figured out it's the DU that's causing the "in use" message.

Yes that issue is fixed in Monterrey, but then in Monterrey when one uses Text Edit to "open recent" file, Text Edit crashes....even in 12.3.1. I'm wondering if that will be fixed by the time Apple releases Monterrey successor :)

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).

Late to this, but I have the issue on 11.6.8. (MacBook Air M1)

Thinking back, it I think it started when I started do TimeMachine backups to a directly connected LaCie SSD. I used to do backups to an external drive on my iMac. I've stopped that backup (but left the drive attached) and we'll see what happens.

My MBA is mostly my traveling computer and I haven't been doing much of that recently :) But once a week I disconnect it from the LaCie and power, close the lid and go out to my patio for a Google Meet meeting. It usually took me about a minute to launch the Meet website (or Meet app) and then I'd get the crash. So I figured it was something to do with Meet and have been chasing rabbits down holes :)

Last weekend, as I opened the lid an my neighbor shouted "hi" over the wall and while we talked (computer was idle) I saw it crash.

Backup to the LaCie was so I could take it with me on a trip in case I had issues and need to restore the disk. But I can do without it or just make a CarbonCopy clone before I leave on a trip.

Just a data point. I ejected my external hard drive, put the MBA to sleep and as expected it crashed shortly after I raised the lid,'

Left the drive disconnected, closed the lid and after re-opening it did not crash.

So it is (at least in my case) related to the external drive.

Oh, my two images are missing...

Here the content of the file "eject"

Example desktop screenshot with executable "eject" script