I can run what seems to be anything else and YouTube at the same time for example (Ableton or stand alone synths like Arturia Pigments, Kontakt etc) but not VCV Rack. I have my Windows 10 set up for non-exclusive. What might cause this?
Not sure exactly what you mean by “set up for non-exclusive”.
I just tried using Rack audio in and out through my Focusrite (on ASIO) processing Audio from an outboard synth, sending to my monitors on the Focusrite outputs, and ran YouTube at the same time, also outputting audio to the Focusrite with no issues and no particular setup (that I’m aware of).
Also tried WASAPI out from Rack on a generative patch and Youtube at the same time without issues.
What hardware? Different drivers handle multiple clients differently. My Focusrite works with Rack and ASIO and other apps like browsers. I never have trouble so i never investigated how it all works under the hood…
You can set windows up to allow an app to take exclusive control of the audio. I am running a UA Apollo Twin but also have an 18i20 routed through it for the extra channels. If I run Ableton for example and then YouTube, YouTube shows up as Tracks 3/4. If I close Ableton and open Rack, YouTube stops working.