So here's something I'm having a hard time finding. As a musician, I have a stomp box board. A lot of my effects are digital and reprogrammable. I'd love to to just "keep them all connected" to a usb hub, then connect a single usb cable back to my phone or computer.

When doing so, I instantly introduce ground loops. MIDI gets around this by having opto-isolation as part of the spec, but MIDI-over-USB of course negates this. I would love to have a USB hub that was opto-isolated for both power, data, and ground!