Imported baked fbx anim makes weird quick move during animation and go back again?

I have made an animation in Maya, baked it and imported into unity 2017. Works very nice, but after the end and it loops, it makes a very weird as if it moves to another position very fast just to go back. I can't see this happening in the maya anim, nor in the imported anim i Unity inspector. Anyone knows what it can be and how to fix it?

Any direction would me much appreciated.

Cheers, Dan