Stutters in combat with people

[McCheesyBirdMess]

About a year ago I used HDT and everything worked smoothly. Eventually I started Skyrim fresh and HDT didn't make it back into my modlist.

 

Fast forward to now, got HDT again and can't seem to figure out this strange occurrence. While walking around towns or the wilderness, everything runs perfect. As soon as I get into combat with a humanoid creature (Bandit, Reaver, etc.) I get these massive stutters, about 2 seconds each. They persist until about a minute after all combat has ended. Fighting anything else (Dragon, Ash Spawn, Wolf) causes no issues. Also, only my armor has weights applied to it for HDT, everyone else's armor is just vanilla. Any ideas?

 

Using HDT 14.28 and everything that came with it (i.e. no custom .xml)

XPMSE 2.50

UNP HDT Body http://www.nexusmods.com/skyrim/mods/21199/?

 

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