Hello David Glynn,
Good to see you in Microsoft Community.
Let me help you restart your audio device.
1. In Windows Settings
Win + I to open Windows Settings*, and navigate to the interface as shown below, and enable the device.*
2. In Sound settings
Win + R to open "Run", type "mmsys.cpl" and press Enter to open "Sound", right-click the empty space > Show Disabled Devices*, you will see all your audio devices, then right click on the device >* Enable*, and press “OK” to exit.*
If anything is unclear, please feel free to leave your messages here.
Best Regards,
Mosken_L - MSFT | Microsoft Community Support Specialist