Offizieller Kommentar
Can you put the unit into firmware update mode? Press and hold the USB 1 STOP and RELOOP/EXIT button on deck one while powering-on the XDJ-RX. If it does NOT enter firmware update mode, then the unit will need to be sent for service. If it DOES enter update mode, please try and re-flash the firmware (download available here).
If you are able to update, but the unit still won't perform properly, please send it for inspection and servicing.