Hello, Louis Cartland
Welcome to the Microsoft Community
Thank you for your feedback. I read your description of the problem.
I understand the trouble this problem has caused you. According to your description of the problem, if the audio problem still occurs after restarting, there are two possibilities. One is that there is still a problem with your current installed driver, which causes the audio to not work properly after restarting the computer. The other possibility is that there is interference from some third-party software, which causes the problem to reappear after restarting.
Based on the above analysis, I suggest that you try the following methods to troubleshoot the error first, which may help your current problem.
Method 1. Update the driver
Find your audio device in Device Manager
Right-click the device and select "Update Driver".
Select "Search automatically for updated drivers". If Windows does not find a suitable driver, visit the official website of your device manufacturer to download and manually install the latest driver.
Method 2. Your current problem may be caused by some third-party software interference. Therefore, I recommend that you perform a clean boot to rule out third-party software interference. Please follow the guide in the following link.
How to perform a clean boot in Windows - Microsoft Support
Disclaimer: A clean boot starts Windows with a minimal set of drivers and startup programs. It helps determine if background services are interfering with your game or program and isolate the cause of the problem.
After performing a clean boot, test to see if the audio problem persists.
Finally, you can also try entering Safe Mode, which starts Windows in a basic state by using a limited set of files and drivers. Observing Windows in Safe Mode enables you to narrow down the source of the problem and help you resolve the issue on your PC. You can refer to the link below for how to enter Safe Mode.
Windows Startup Settings - Microsoft Support
Best regards
Brian - Microsoft Community Support Specialist