USB ports not working after installing Sequoia

I would try booting into Safe Mode to see if helps.

Use safe mode on your Mac - Apple Support

One further update - tried daisy-chaining my USB drives (which all have USB-A connections) through one of the two USB-C connections on the back of the iMac. They're now back up and running, so whatever the problem is, it's with the USB-A... is it possible that this is a hardware issue that just COINCIDENTALLY manifested in the same hour that I upgraded to 15.0? I hate that I'm even considering this.

Not a hardware issue. I have been down this route. It's causing havoc with 3rd party usb connections and lots of other manufacturers. My havit wireless mouse does not work through my base hub and only via the rear usb connection on the mac mini. Terrible. Hope they sort it out quickly for us guinea pigs. Usual scenario folks. Don't jump in for at least 6-9 months.

I have this exact USB disconnect problem after Sequoia install with my audio set up. I'm running USB from a MAC desktop to a DAC, then balanced interconnects to an amplifier, have tried different USB ports. My amplifier will connect and play Apple Music tracks for about 5 seconds, and then disconnects. I originally thought this was an amplifier problem and switched out my amplifier to another. Same problem with either amplifier. I could try different cables and DACs, but I don't think the equipment is the problem. So far the only way I have to play music is with bluetooth earbuds--far from satisfactory. Apple needs to fix this.

Same problem here, I have mechanical keyboard and wireless mouse both from Logitech, after Sequoia upgrade both keyboard and mouse get disconnected/connected maybe 4 times in 15 seconds and then disconnect completely, I disconnect my Ugreen hub and reconnect it again, keyboard and mouse works for few seconds and repeat the whole story again.

I also notice some lagging in performance after the upgrade.

Sequoia is a true nightmare, I really hope Apple team fix these issue ASAP.

I'm having similar issues with my 2020 iMac 27 inch, ever since upgarding to Sequoia about a week ago. My hard drives disconnect randomly, my microphone interface produces a very robotic glitched sound, my sound stick DAC disconnects as well. All of these bar the DAC are connected through a USB hub, but the fact that the DAC disconnects as well leads me to suspect that this is not a simple case of a Hub gone bad.

Another update on my USB problems. Sequoia was updated to 15.0.1 today. My iMAC Pro (2017) worked perfectly with my sound system before Sequioa--now a garbled, one channel input to my sound system drops after about 5 seconds. Running Schitt Audio Yggdrasil DAC connected to iMAC Pro (via Schunyata USB cable), DAC is connected to a Schitt Ragnorak amplifier (via Audience AU24SX cables). After the Sequoia update this morning, I had high hopes, however same problem as before. The DAC seems to provide a signal to the amplifier, however after a few seconds of low volume, garbled right channel audio, the amplifier loses signal, and that's it.

Same problem here. I have a third party Kingston Thunderbolt 3 docking station for my MacBook Pro, and all of a sudden I lose my network, screens, and it brings me back to the login page. Extremely annoying! Especially when I am on customer calls doing demos, this is not okay. Apple team needs to fix this ASAP as it is causing lost productivity.

Same issue, when trying to connect my interface into Logic 11, and even transferring video files from my camera to my Macbook, its really a guessing game as to when it will connect. I've tried swapping cables etc to confirm its not hardware. has anybody figured this out yet? Apple M1 Pro, Sequoia 15.2

The worst of it is, I can’t access my Time Machine backups to roll-back because, erm, they’re connected by USB! Was really hoping 15.0.1 would give us some joy.

For the record, tried safe booting. It doesn’t make any difference.

Can you explain a bit more on how you did this? I have had the same issue since updating to Sequoia.