you may want to uninstall the complete AMD drivers using Windows Control Panel and DDU in safe mode. Than reinstalling the AMD package drivers except for the HDMI driver (Use Custom Installation and unclick HDMI audio). You also might want to disable Windows Update from automatically updating your drivers through Windows Update.
But if you don't install the HDMI audio driver you won't have any audio from your AMD card. Have you tried just disabling the HDMI driver in Device Manager? Also in Conrol Panel under Sound you can disable the Audio device that is giving you problems.
I used DDU and installed the drivers (unticked the Audio driver). It appeared again. Why this happened?
I disabled the amd audio device in device management.