Hello,
I have dusted off my UX2 after several years of not using it.
I got the Surface pro and ran into the same problem as you.
It has only one USB port and I am trying to use a MIDI controller at the same time with UX2.
Tried several HUBs, 2.0, 3.0, powered and unpowered.
Same problem - garbled output.
Did you ever find a solution?
Thanks.