Why does Planetside: Aftermath stutter during stealth movement?

While performing precise stealth maneuvers, the screen would suddenly hitch for a fraction of a second, which is lethal in this game. I tried lowering all graphics settings to the minimum, but the stutters persisted, leaving me anxious. I ran the GamePP Peripheral Driver Conflict Detector and found lighting software scanning the USB bus, so I disabled it and enabled raw input. RTSS showed the spikes disappeared, with frame times stabilizing at 33-40ms per FrameView and AIDA64 reporting temps at 52-58℃.