Some Mac users who upgraded to macOS Monterey this week are experiencing problems with USB hubs and other USB devices working correctly on their machines, according to scattered reports on the Internet.
On Reddit, Apple Developer Forums and Apple Support Communities there have been several reports of these problems. In some cases, users report that after upgrading to Monterey, the USB 3.0 ports on their hub no longer work, while the HDMI, USB-C and other hub ports continue to work as expected.
In other user reports that have appeared online, the USB hubs are not working at all. Some problems even involve Apple-certified hubs. In other cases, the USB hubs work except for the power supply port. In some cases the extra connectivity provided by external displays stops working, especially the power port.
Many reports come from owners of Macs with the M1 processor, but not all. Some users are reporting similar issues on Intel Macs. Judging from user discussions, USB issues were reported in early beta versions of Monterey, suggesting that it may be due to a legacy bug that Apple has yet to fix.