Weird behaviour when powered from iPad

[TheNothingMan]

Hello, I'm currently fiddling around with creating a portable setup of an audiointerface, speakers and my Pedalino in a small suitcase. It should be used with my iPad, and everything gets connected via an USB C hub. This hub is powered by a powerbank, loads my iPad and should power the speakers as well as the Pedalino.

I noticed that some controls don't work correctly - hitting one switch activates actions of another one etc. Some switches work fine. I already tried different cables. The problem doesn't occur if I power the pedalino from the second port of my powerbank without going through the hub. It also works if my iPad is not connected to the hub.
So I figure it must have to do with the iPad connection. I didn't update firmware to latest yet, but I wonder if anybody here has successfully powered his Pedalino from an iPad.

I will do some more research in the next days and report if I find a solution or more information.