Ever since they added the "universal search" thingy, their NAS do that anytime they reach a decently large video file. Even if you turn down search indexing, media indexing, media thumbnails, ... It still kills itself with no throttling processing those files.

May or may not be what you encountered, but had a customer caught by this and found out the hard way you can't stop it. My issue is not the processing, it's the throttling, it's so crazy how the entire NAS gets taken down for like ten minutes (and that was on a racked xeon model), no samba no nfs no nothing answering anymore.