Nvidia instant replay not recording game sound anymore

I'm 99% sure it'll be something to do with the razer headset. It always is. (Razer Blackshark V2 Pro) I recently noticed that my sound got quieter in some games, like terraria. While in Left 4 Dead 2, it got louder somehow. And now my recordings dont get any game sound, only my microphone. As well as the fact that the entire time I've had this headset my microphone quality is terrible. While typing this, I realised that as usual, the audio device just decided it felt like changing to something else. It switched from "Speakers (Razer Blackshark V2 Pro)" to "Speakers (THX Spatial Audio) which is a much worse setting. Why does it keep changing by itself? And this still doesn't fix the poor microphone quality. It can barely be heard over game audio. Right at the start of this video you can hear how quiet it is. I have the microphone boost on full https://www.youtube.com/watch?v=AU4hNTMnFtc