USB won't show analysed BPMs and Waveforms on XDJ RX.

Hey, I've always analysed my tracks on rekordbox and then exported them to my usb to be played on CDJs and has always worked fine. However I just bought myself an XDJ and when I plug my usb in, the tracks come up as not analysed, with no waveforms or bpm details. Occasionally one or two tracks will come up analysed so i'm not sure what happens.

Cheers

GoldiRoxs