Hi.
It' the same at Genos as well, if startup with other than the 'bottom stick' inserted at the same time, it will change USB#.
My 'workaround' is to pull out the front usb after power off the keyboard, and not insert it again before it's powered up again. As I only use the other USB ports to 'workspace' to test and try, and when happy, transfer to internal memory or 'botom usb' for permanent location. 😊
The good thing is, that when run any OS update, it's not nessesary to remove or use the bottom usb (USB1), as long as the update file(s) is in the root of other usb-stick, i.e. USB2, Genos will find it anyway. 👍