The BIG FIX for these issues is:
You have, or installed a NVIDA graphics card.
On install, Win10 recognizes this, and disables your PC on board audio in the PC BIOS setup, as it wants to assign all audio to the NVIDA, to go to the HDMI video interface. Device Manager will not let you even see your other PC on board audio devices, or install anything related, including running the popular SoundMax driver install software from all PC vendors. (This is Analog Devices audio chipset on many boards, and will report no hardware devices available).
Reboot the PC, F10 to the BIOS, Advanced Options, on board audio will be set to disabled, set enabled.
Future win 10 install should recognize this, and provide the option, which audio to use, and also not mess with the BIOS settings.