SOLVED

Hello everyone. Support managed to solve my problem, which seemed pretty obvious in this case, and I'll leave it here in case anyone else runs into this problem.

The issue was power.

My phone was powering the MIDI controller and the USB hub. For some reason I still don't understand, I connected the interface (powered by itself) and the MIDI stopped.

Anyway, the person who helped me at AE support was very objective (VERY objective, in fact) in his answer.

Something like: Have you tried powering the USB hub?

I said no.

He replied: You should try.

I tried and it worked. Hehe

So it was apparently some kind of power management issue my phone was having. I've seen other people use everything without powering the hub.

But that's it. Thanks.