I had the same problem in some earlier builds when I would run systems with more than 5 machines.
Here is a quick workaround0:

Try building a cue which puts all machines at InFrame for new file. Then a wait cue which reassigns Sync ID to slaves and triggers Play on master.
For example:

Cue 1: All Inframe
Cue 2: Slave to sync ID and Master to Play
Cue 3: All Inframe change file
Cue 4: Slave to sync ID and Master to Play

Make the wait time .1s for cues 2 and 4.

Or if you build a crossfading cue stack, build the upper layers invisibly into lower cues
For example:

Cue 1: Layer 1 all Inframe
Cue 2: Layer 1 full, master Play, all slaves sync 1, Layer 2 zero all Inframe
Cue 3: Layer 2 full master Play, all slaves sync 2, ...



Also, what version of Catalyst are you using?
Is the Hog Artnet on the same network?
Are you also running HogNet on same network?