How can I fix the issue with M4 MacMini - USB speaker & microphone not recognised?

What USB-C to USB Adapter or Hub are you using to plug the speaker into the M4 Mac mini..?

Test the speaker using a USB-C to USB-A adapter plugged into one of the M4 Mac mini's front ports.

for some examples:

USB-C to USB Adapter - Apple

https://www.amazon.com/dp/B07PDLQ555/ref=sspa_dk_detail_0?

https://www.amazon.com/dp/B08Z768LCW/ref=sspa_dk_detail_1?

https://www.target.com/p/philips-usb-c-to-3-0-usb-a-female-adapter/-/A-79804275

I have this same issue, only that I did not try to use Jabra on my MacBook Pro M1 and now it already runs 15.4.1

I am not using any adapter.

Jabra Evolve2 85 included an USB-C-dongle.

I think it is the Jabra Link 390 USB-C

I use my Jabra with the adapter on my Mac mini M4 and it stoped working after an OS Update.

On my MacBook Pro M1, I installed the Jabra Direct app, restarted the computer and checked to see that the Jabra-app had no updates. Then I incerted the USB-C-adapter, but nothing happens.

Is it Apple who shall fix the issue, or is it Jabra who will step up and supply an update?

If other USB devices are not working when plugged into your Mac..?

Disconnect all USB devices > Startup in Safe Mode > Restart normally > test one USB device at a time.

have a look at > Start up your Mac in safe mode - Apple Support

If other USB devices are working when plugged into your Mac..?

contact Jabra for support > https://www.jabra.com/support