Hang part way through frame

[EngineHouseVFX]

Image attached to show the problem, Max / Octane will just stop rendering a frame part of the way through. In most cases it will render a few frames (in this instance it made it to frame 13 for added spookiness!), and then it will get part way through a frame and then just stop doing anything. The window doesn't close, the computer doesn't hang. As far as I can tell the graphics drivers haven't crashed, although it would explain it I guess? I can keep using the machine absolutely fine after I cancel the render and close Max. If I restart Max I can carry on rendering the sequence until it hangs again.

What makes this more frustrating is that this now happens on two of our workstations, so it is less likely to be a hardware problem. The cards are already set to low priority, we have more than enough power from the PSU, the machines are water cooled and temps are around 30 degrees when rendering.

The only common thing that has changed recently on both machines is Octane 3 as opposed to Octane 2, and we've updated to Windows 10... perhaps there's a problem there?

Any thoughts or suggestions would be very welcome as it's really holding us up at the moment.