How do I remove anim key on root bone?

Hello,

I have 2 weapons, rigged and animated, ready to align to prop bone in game. both have a master root node with no animation in 3ds max. Both exported the same. Inside unity, the root of one weapon is clean, while the other has a key or two on the root. There is only a single root in both files. The problem fbx maintains its extra key even when specifying "remove single key" in fbx exporter, also even when exporting with no animation.

Thank you for your time.

Update: When i pull the problem fbx into a totally separate unity project, the root key is gone. I have tried reimporting and deleting/re-adding in the original project, to no avail. Does this ring any bells for anyone?

Update 2: It turns out there are keys on the root in the weapon @animation file that accomanies the asset. this is why the key doesnt show up in the animation editor when the bind pose is placed in a separate project or directory. the fbx of the animation is baking out a key on every frame of the root, even though there is no animation on it. This doesn't happen on the other weapon, even though they are rigged and exported in the same way.

I guess this is a fbx/max problem rather than Unity, sorry to waste your time!