Why does MX vs ATV stutter during intense combat scenes on S790 SSD?

Frame time jumped from 8ms to 45ms during combat. It was a mess. I tried disabling the camera in Device Manager, but it killed my stream. I used GamePP Peripheral Driver Conflict Detector to set Razer Synapse to manual start. RivaTuner shows frame interval stable at 7-12ms. OBS monitor confirms CPU usage at 65-72%. The stutter is gone.