In windows 10, you can disconnect the microphone portion completely and that seems to fix the problem. You'll notice that although the post is old, there is a comment about someone trying this with Bluetooth 5.0. If you are using Bluetooth headphones and they are also being used as a microphone, there is just not simply enough bandwidth in the headset to do both. Neither the basic nor the complete uninstall worked today. I will attempt to do a basic uninstall, and let people know how it goes. Upon reinstalling Discord, the problem was solved until today. This entailed uninstalling the app, then manually removing the registry entries and app data (Things Discord should be deleting when they uninstall, but that is a different issue.). Two days ago, I did a complete uninstall of Discord. Neither of these are what I would call a solution, as it negates the features of being able to isolate the chat sounds. Also, if I go into the sound device properties check then uncheck the 'Disable all enhancements' box and click apply it will start working again.

If I change the output to the headphones, the sound for the other devices comes back and works fine.

In the Discord Voice and Video settings, the headset output is listed as the certified one, and the headphones (game output) is somewhere else in the list. Like what I assume many of you all have, there are two separate outputs for the headset, a game and a chat output.

I am using the SteelSeries Arctis Pro Wireless headset, which is 'Certified' by Discord. My discord started doing this about two or three weeks ago.

Skype lowers game volume