Animated displacement inconsistent

[Ryan Day]

I've got an animation set up with a number fade for some motion in a displacement map, but it doesn't seem to work consistently. Sometimes when I render out part of the sequence it doesn't animate, and sometimes it does. I haven't been able to figure out why yet; any clues where I should be looking for the culprit? The animated node in the material is active, I've tried executing the geo node again before hitting render, and changing the 'to' value just in case the scene units got buggered somewhere along the line, but I can't figure out why it's not working sometimes.

I'm still running KS8 at the moment if it makes any difference; should be the most up to date version of KS8.