Then you should give pipewire a serious go with multiple channels. It's way better than MacOS stack which doesn't really do independent multichannel by default. There's an API for it that some paid apps use that lets you do it. Meanwhile pipewire just lets you connect whatever wherever. I managed with pipewire to get lower latency on Bluetooth headphones than MacOS allows at all.

What happens with 6 channels? You just connect them where you want and it works.

I'd happily do that, and give it a whirr. I have no qualms against that.

Unfortunately I no longer have my primary desktop (Linux) system, and no external audio interface to play with at the office.

If I can borrow something from my friends, I'd love try to give Pipewire another go.