Problem DR on one node

[tricky]

Hi y'all.
Gone through our entire suite of machines today and installed Max2019.2 along with VRay 3.60.04. All nodes are rendering using DR without an issue apart from the last one (which just happens to be one of our faster machines - a dual 8/16 core XEON).

The node is added and I see 'scene loaded; starting render' but then a few seconds later I get a 'render host is not responding' message and then it just continues in the same loop.

Any ideas? It's been a few years since I've had this sort of an issue.

[tricky]

OK - now it seems to be working. Can't say exactly what I did though. I sent a simpler 'test' scene to it which worked, then my more complex scene seems to be working.
Gremlins - don't you just love 'em?