So I use 2.1 studio monitors (Left, Right, 10 inch sub) to output sound on my pc through a focusrite scarlett solo interface. In most games I play I don't see an option for 2.1 audio. What would be the best setting to choose? Thanks
You can just use the stereo L+R setting it will be the best, your speakers have a crossover that will handle the full range of audio and distribute the lows to the sub and mid/highs to the speakers.
You only need to change it if you use the full surround outputs, I believe the only options (on most on-board audio) are "Stereo", "Quad" (stereo + rear surround), "5.1" (using all 3 connections on the outputs, Front L+R, Rear surround L+R, Center & sub).