Steps to reproduce:

1. Open the attached project
2. Open 'StartSetSpeed' scene
3. Select 'unitychan' game object and remove the script component
4. Open 'Animator' window
5. Open 'Parameters' tab
6. Set the 'OffSet' parameter to be anywhere between [1..1,000,000]
7. Play the scene, notice the animation is playing as it is with CycleOffset set to 0
8. Change the 'OffSet' value to a bigger value [2,000,000..5,000,000]
9. Play the scene, notice the animation is playing with like it was lagging