Since, this system is a layer outside the kernel, just a bunch of normal applications I don't think this would work as smoothly. I think you'd need a custom storage server to serve the audio card from the other machine. It doesn't by default serve the entire host filesystem.

That said, I think the goal of upspin is that you easily can re-use its interfaces to do things like this. There are already some guides about writing custom shim storage servers like that (the main example being a webcam server), but I think this sort of experimentation is still in the early phases.