So i am using NDI tool and OBS to record gameplay, and what I want is for OBS to only record gamesound, not music or communications from discord ect. 
And I can get it working, but it seems very random. When i set it up and its working, the next time i start my setup, NDI tools suddenly takes all audio coming from the main PC, not just the audio output that was being recorded the last time. 
I then spend 30 minutes opening and closing NDI tools (Opening and closing it untill its working correctly is the only fix i have found) only for it to suddenly do as its supposed to do, and then the next time I start my PC, its all over again... What is going on, am I doing something wrong??