Cues don't save

Hi all

All of my tracks are analysed in rekordbox beforehand, made into playlists and exported to my USB keys. When I then go and play on CDJ3000s, I set cues, loops etc on the players as I go.

When I've finished my set, ejected the key (properly!) and get home, I plug the same USB into my computer and all of the cues, loops etc that I set on the players are gone.

Obviously. hugely annoying and also incredibly difficult to manage if I have some tracks on other keys and in multiple playlists.

Why aren't the players saving my cues etc to my keys?

Thanks