For me it's not just games or streaming, it's all audio software. I can hear myself in the microphone, I can hear the second person connected by an audio interface that I use for a podcast that works on an Intel Realtek drivers PC but the same configuration isn't working on this PC.
I suggest you try to go to Control Panel, Hardware and Sounds, go to Sounds, then see if you have stereo as an option. Unhide all choices too but I don't have stereo audio drivers even though it says AMD High Definition in my Device Manager.
I've tried to uninstall the software Adrenaline Edition, uninstall the audio drivers in Sound and Bluetooth and then reinstall them. Download them first to make sure you have them but it might fix your issue. It didn't mine. The whole reason I bought this PC was because of AMD Radeon graphics and to use it for podcasting and it's not working so I'm out $850.
I've tried rolling back the drivers, updating the drivers, try booting in Safe Mode and see if it works also. Good luck mate. If you've found a fix please let me know.