Lemorele HUB: current overload on USB-C port when iPad battery is 100%?

I have iPad Pro, with a Lemorele USB-C hub with USB-C power port (9 in 1 - TC92).
My Steinberg UR44c sound card is connected to the other USB-C port, which takes power from the hub.
Everything works perfectly as long as the iPad is charging, but… when the iPad’s charge is 100% the sound card signals that it has power problems, flashing and resetting.
It goes away immediately if I physically unplug the power cord.
Any idea?