What Rharv said - plug in before you turn on the computer. There are also some Line 6 videos on their web site as well as You Tube, showing how to use their interfaces. I don't believe any of these deal specifically with BIAB or Real Band, but they're generic enough to point you in the right direction. The UX1 should plug in via USB just like my UX2 does. I have mine set up to basically become the sound card (this allows use of the very low latency monitoring if desired).

Good luck

Bruce

PS - sorry for my previous typo - ... is EVER plug and play (not EVERY)


Macbook Pro 2018
2.6 GHz 6-core Intel Core i7, 16 GB RAM
OS Monterey
BIAB for Mac 2022