Disabling Realtek audio notification on Windows 10

Go to Settings > System > Notifications and actions and under Get notifications from these senders, scroll down and turn off Realtek HD Audio Manager

I found a solution here that worked for me. Basically:

1. Open the Realtek HD Audio Manager through the Control Panel.
2. Click on the lowercase "i" on the bottom right of the Audio Manager window that pops us (just above the OK button).
3. Uncheck "Display icon in notification area".
4. Click OK twice to exit the Audio Manager.

For those with no success with the previous suggestions: In my case (Windows 10 Version 1803 build 17134.254), what finally did work was to go to Task Manager > Startup tab, and right-click on the Realtek HD Audio Manager and select Disable.