Users of macOS 12 aka Monterey complained about some problems with docking stations and hubs for port expansion. Corresponding reports are currently available from Apple (in the developer forums and official support forums), Reddit and other websites.

Affected people said that their expansion box can still run without any problems under the macOS 11 alias Big Sur, and it still provides HDMI, USB-C and card reader slots, but USB is paralyzed in the USB-A version 3.0 port. A user wrote that his screen on the Mac mini works as usual under Monterey through the HDMI port of his usual USB-C hub, but the USB 3.0 port does not work on any hub he owns. It is said that the MacBook Air with the M1 chip is also affected, so it obviously has nothing to do with the hardware used.

Another interruption involves power delivery via USB-C (Power Delivery, PD). There should be individual hubs that no longer provide juice under macOS 12. In rare cases, the screen connection provided via USB-C will also fail, while the mouse and keyboard continue to work strangely via USB-A. The Ethernet connection is clearly not or rarely affected.

What all machines have in common is that they run macOS 12.0.1, the Monterey version that Apple is currently delivering. Most of the reports are from M1 Macs, but Intel machines also have problems. During the Monterey testing phase, users have reported USB errors to Apple, but they do not appear to have been fixed. This problem sounds like a driver problem; which components are specifically affected have not yet been leaked.

Apple is currently developing macOS 12.1, which is Monterey's first major update. It is unclear whether this will solve the problem. Users who urgently rely on its USB 3.0 port can only avoid upgrading to the macOS 12 alias Monterey for now, and continue to rely on the available macOS 11 alias Big Sur.