Hallo, this is my solution:
- Right click on sound icon
- Click on Sound settings
- Bottom: Additionals sound settings
- Click on default audio output (in my case Realtek Audio) - click on properties button
- Click on properties ...
- Change settings...
- Update driver:
- Try to find new driver in PC (not automatically)
and you can install Microsoft audio driver:
RESTART.
Done.
Sorry to be so long in replying. Eventually I reinstalled Win 11, which restored the audio but caused several blue screen crashes. Finally, I took the PC into the retailer where I bought it (I have a service plan). They installed an additional SSD that effectively separates my apps and data. That has resolved the audio issue - but then the PC started shutting down cold for no apparent reason! I wondered if that might be overheating, so I propped up the rear of it to see if that keeps the vent underneath open.