I got mine to work. I had uninstalled Nvidia drivers, uninstalled the hdmi audio drivers, restarted, and nothing would work. then today I did a rollback to the hdmi audio driver and now it works.
I have found a solution works for me!
1) Goto Device Manager > System devices
2) Here you can see High Definition Audio Bus right click it and Update driver
4) ** Click Let me pick from a list of available drivers on my computer **
6) Click Next and you are done.
Have another solution. Nothing helped me from the previous answers. I had upgraded my AMD drivers to the newest 20.12 and HDMI Audio to my TV disappeared. The solution for me was to downgrade to my last driver version (as far as I remember) 18.1.1 https://www.amd.com/en/support/kb/release-notes/rn-rad-win-18-1-1. Maybe I will be able to upgrade to a higher 18.xx version but I don't want to take that risk anymore.
P.S. I tried to update my BIOS to the latest version, to install AMD 17.xxx drivers, to update Audio Bus from Device Manager - and nothing helped.
Wow. Thank you for this. Spent they day trouble shooting my BENQ PD3200Q monitor and when I realized it wasn't the monitor next went to the graphics card. Found this forum in minutes. Such a relief! Thanks everyone and especially VACHE!
This is exactly my problem. when I check the "AMD Radeon Setttings, System, Software, AMD Audio Driver Version". It says the Audio Driver is NOT AVAILABLE.
On my board too, I thought it was a problem with windows, so I formatted the entire machine for the sake of this problem, and it is not the first time that driver update affects PC audio! They're doing very poorly optimized it!