macOS Monterey broke webcams running MJPEG

Hey there t_fox_19,

We'd like to help get your webcam working correctly with your Mac. Let's start with some basics:

1. Does the same issue occur if you directly connect your webcam to your Mac, without going through the hub?
2. Has it ever worked when connected to the hub, and if it did in the past, when did this first start?
3. Any issues using the built-in webcam for the same purpose?

Take care!

HI t_fox_19,

As your built-in webcam works without any issues, along with the external webcam having no issues when directly connected, the issue points towards the USB hub.

You mentioned that it's a USB 2.0 hub, which means it's significantly a slower connection compared to USB-C. This could have a role in what you're experiencing.

Another thing to consider is compatibility with not only the latest macOS Monterey version, but also with the third-party webcam, along with the connection it uses. For more help with confirming all of these compatibility points, we recommend contacting the manufacturer of the USB hub.

Have a good one!

I believe this is an issue with Monterey supporting devices that output MJPEG, and/or a UVC driver implementation issue.

I have UVC compliant cameras that have MJPEG and UYVY output support. They are able to output UYVY just fine via USB 2.0, USB 3.0, direct connection, and via USB hub in USB 2.0 or USB 3.0. The MJPEG option does not exist. You cannot even find the device via any app or utility.

Big Sur, worked just fine. Monterey for some reason has broken this, and there's no explanation. Camera manufacturers have just recommended plugging in to USB 3.0 since it usually forces their hardware to output something other than MJPEG.

It would be helpful for an engineer to take a look at this, as there are many cameras (expensive ones, too!) that have suddenly stopped working secondary to this upgrade. It's extremely frustrating for us to downgrade to Big Sur, as that requires having a recent enough time machine backup so that we don't lose all our files.

Yup, Monterey broke my Logitech 4K Pro webcams, they only work in real-time with no dropped frames at 1080p now, on both Intel and M1 MBPs. Outputs options in OBS, for example, are far more limited when compared to Big Sur.

Logitech says the issue is on the OS side.

Some even professional PTZ room cameras only provide MJPEG when operating in compressed mode.

The compressed mode is automatically used for USB 2.0 High Speed transmission.

That is useful to transmit USB Camera signals over longer distances than 3m or switch it between different Laptops because the availability of professional USB 3.x SuperSpeed Extenders as well as switching solutions is very limited.

Especially at universities that is a common way to equip lecture halls.

I did some tests and it is very clear that Monterey broke the support for MJPEG for USB UVC devices.

I assume that this issue will become for educators a massive problem as soon as they receive the Monterey update.

It would be great to see a very soon fix on the OS side.

I have the same issue. Both of my Logitech webcams (C922 and the Apple 4K magnetic webcam - which is sold by Apple) were working fine with Big Sur and connected the USB and USB-C ports on my LG Ultrafine 32 inch monitor and now are extremely blurry after I updated to Monterey. I plugged the Apple 4K magnetic webcam with a USB-C to USB-C cable directly to the 2019 MacBook Pro and the same issue persists. So this is not isolated to just using a USB hub.

This appears to be a known issue that still hasn't been resolved.

Can you please help as I rely on the webcams for my work.

Thanks.

Exactly Roland_br!

Because I’m now using an M1 Pro, I can’t even roll back to Big Sur. :/