99.99% of the time I use my Soundblaster sound card for audio, but I do have the builtin Realtek audio chip turned on for the very rare occasions I use it. I was surprised to find an app in the win10 Start Menu called Realtek Audio Console that I'd never installed. So I search the store in win10 for the word realtek, and don't see it. I try to fire the app up, and it says it won't work on this machine. Hmmm? Everything audio seemed to be working fine, so off I went to investigate.
I didn't find anything out on the Realtek site, though I had a very hard time connecting to it, eventually succeeding in Edge. I finally found a post that explained the Realtek Audio Console first became available in the store around August, and that it requires something called UAD drivers, which take the place of the traditional drivers from Realtek. Those Realtek UAD drivers are, if you're lucky, available on the support web site for your PC, motherboard, laptop etc. If not you'll have to Google -- the Station Drivers site was mentioned A Lot, and it turns out they were offering a download that seems like it was originally from the MSI site.
Installing the UAD drivers means your old Realtek audio drivers will be removed, and afterwards the Console app should work. The app does not seem to offer everything the old Realtek audio mgr. in Control Panel offered, and several files used by the old drivers with DTS in their name vanished, suggesting that these newer drivers lose some decoding capabilities. Reports I found varied on whether the audio sounds better with the old driver or the new, but most agreed that it does sound different.
My 1st guess is that the new drivers are a response to Microsoft's new directives on how drivers should work, starting with win10 1809. That's what caused Intel to redo most of their graphics drivers very recently. My 2nd guess is that win10 automatically installed the Realtek Audio Console app when I upgraded from win1803 to win10 1809, though it did not do anything about the preexisting drivers, nor did it warn me or otherwise say anything about this app when it was added. Which is the reason for posting this... I highly doubt I'm the only one with this new app installed [surprise!], and I'm not likely the only one who fired it up just to find it didn't work. If it happened to you too, then hopefully you'll now have abetter idea of what's going on.