XDJ Rx3 - Rekordbox Link & Midi issues

Hello Recently purchased an XDJ RX3 but I need some help please. 1. Updated all the drivers & firmware but I can't get the controller to connect to the Rekordbox. When I select source the screen on the Rx remains blank. I can select link in RB but the the devices ar the bottom remain greyed out 2. I have RB5 and I was under the impression I can still use stems. When I select midi there is no device being picked up. Any advise would be great. Thanks