Why does Rule the Waves 3 frame rate drop from 60 to 45 FPS during parkour?

Every time I landed a jump in Rule the Waves 3, the screen jitted and frame rate dropped, causing anxiety about the visual experience. I tried lowering graphics quality, which stabilized the frame rate but significantly reduced visual fidelity, causing frustration. I then used GamePP Power Plan Switcher to switch to High Performance mode and manually locked the CPU core voltage. This prevented the 0.05V to 0.01V fluctuation that was causing instability.