Not sure if you are using a cluster of computers but I had a similar problem and for me the issue was that I was using the loopback 127.0.01 address in the LiveLink preset. When running on an nDisplay cluster you need to use the actual IP of the system that’s doing the tracking.
See also this thread: Live Link works in editor but not in nDisplay (using Vive Mars)
But maybe you’ve found it already and solved your problem.