ddj rzx running 2 computers

I am running 2 pc's with rekordbox on both of them plugged into usb a and b but I can only get wave formats on centre screen for 1 of the computers, and the controller won't show the other waves. then it crashes the scrrens on the rzx. My question is does having the same serial numbers cause a conflict? As I was under the impression that I am able to run 2 computers with the same serial number.

eddie