I have never had issues with this before, but all of a sudden, something that looks great inside Spine, looks very weird in Unity.

Track 0 = Idle animation
Track 1 = Hold Item animation (pulls out hand)

Now in Unity I set this using this simple code

var trackEntry = skeletonAnimation.state.SetAnimation(1, spineAnimationCached, false);
trackEntry.MixDuration = 0.3f; // Duration of mix

I have a toggle method, that switches between this and an empty animation.

The first time it just jerks into position. But the position looks ok. When i clear it, it animates smoothly back into the idle pose.
Then second time i enable it, it smoothly animates, but not to the full pose, if you check the video, the hold item animation isn't the same as first time. After that, it repeats the same smooth on/off into the wrong pose.

Any idea what's going on here?

I also tried additive mixing, which looks almost the same in Spine, but this makes it totally freak out in Unity, with arms spinning around.

Also another weird thing is that in Spine, the hand looks rotated in the mix, but it looks ok in Unity.

In the export, I have non-eseential data checked, and animation cleanup disabled. I'm using Spine 4.0 export format, exported from 4.0.17.

This is what it looks like in Spine, with and without additive: