I tested the use of USB hubs on Genos USB slots, but avoid using them due to drive assignment inconsistency.
The hub works, but Genos can interpret the same USB flash drives differently each time when Genos is rebooted. A previous USB2 may become USB3 now, depending on how the Linux operating system recognize the USB flash drives upon each reboot. To make the matter worse, a previous USB1 that holds the Yamaha playlist now becomes USB2, rendering the complete failure of the playlist due to wrong drive path of registrations.