This may be due to an issue we’re facing where channels like temperature may be corrupted. Are you using upscaling by chance?
Otherwise could be a blender issue. One thing you could do is download one of our free VDBs: https://jangafx.com/software/embergen/download/free-vdb-animations/
Maybe the explosion and see if the issue persists. We know for a fact those VDB’s are good and if they work then it’s likely the corruption issue we’re trying to debug. If they break, then it’s likely your blender setup.
Due to the big chunks missing though, I’m leaning towards it being our corrupted VDBs
What version of the software are you on? 0.5.3.1 is the latest.