Are you using the 6.0.3 version of Rekordbox? If so, you will require a subscription to even utilize Performance mode. I was having the same issue until I started the free 30 day trial of the "Creative" subscription plan due to wanting to try out Beatport link.
Now the only problem I have is the waveforms are not showing up the CDJ2000NXS like they do on my NXS2.