XDJ-RR E8305 Rekordbox Link

I have recently purchased a new out of the box XDJ-RR. Here is my problem.

Music library is stored on a WD 2TB External Hard Drive in FAT32 format. It is then imported into Rekordbox. I link my XDJ-RR to my Mac running Catalina. I drag a track onto one of the decks in link mode and I get the E8305 message on the unit.

However, when I plug the hard drive directly into the unit and all of the music plays. Why is this? I have updated all drivers, firmware and even used a different usb cable from the computer to the unit.

Same files being used, Same root location of the files when the controller is linked vs when it is played directly from the hard drive. 

Somebody help. Thanks