Im on Xbox one X. I have the disk, and no stuttering or dropping fps problems at all. Im using a premium (another name for high speed?) HDMI cable instead of the one that came with the xbox. Someone else has already stated to try that. TV is TCL 5 series with game mode turned on. Dont know if any of this helps...just throwing it out there.
this is what im using
https://www.amazon.com/gp/product/B01GCGKI3O/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1