Hi, I assume you haven’t gotten any answers on this (captain obvious)…but have you figured it out?
Same thing just happened to me with my UR12. Only difference is it was working just fine, now I get NO power when I try to use 5V. I get it on USB, but the reverb is horrendous…did you end up needing to replace the unit? I think that is what I am going to end up needing to do…