The last couple of weeks have not been good for Windows 10 updates. First, they had the suspension of the October 2018 Update and then there was a HP driver issue and problem with Intel audio drivers.
I had the audio issue on one of my Dell devices; it only seemed to go wrong during the week after the cumulative update.
After applying the Windows 10 October Update the Intel Audio driver stopped working, I had a red cross through my speaker icon and the driver was on error in Device Manager. The good news is Microsoft have issues a fix for the audio issue which was related to the Intel Smart Sound Technology, and have released a fix via Windows Update.
The fix came down as soon as I checked for updates in Windows Update and didn’t require a restart.