Hi! Thanks for reading!
I would just select the “Stereo Headphones” option in Razer surround (the top one). The other presets are specifically configured for the different sound signatures of Razer’s products…and most of them sound very different from the relative balance of the Arctis 7.
After that you can use the calibration features, since you have Surround Pro, to adjust it to your own tastes. I particularly enjoy the bass boost and the ability to place the virtual speakers, and I always end up moving the side channels a little further to the rear. But that’s just the way my ears like it!
You should also make sure that the Arctis 7’s DTS Headphone X is turned off, and that Windows Sonic and Dolby Atmos are turned off in Windows. I hope that helps you out!