Game is jerky with 40+ FPS

[FireKetchup]

Hello,

I'm having some issues with jerkiness in La Noscea, and to a lesser extent in Coerthas. My issues in La Noscea are usually worst around aetherye camps, but I encounter the problem elsewhere also. It usually occurs when passing through clumps of dense vegetation, but its very inconsistent (some bushes cause lag, while others don't). My framerates have yet to fall below 40, and the jerkiness manifests itself even at 56 FPS. I don't believe its caused by loading npcs and players in the camps, as the jerkiness remains even if I sit near the camp for several minutes.

EDIT: I also experience FPS drops when warping into a city (which is to be expected, I know), but there is no jerkiness accompanying it. I only experience jerkiness in the above zones.

My system specs:
i5-2500k
HD6950 1gb
8gb ddr3 1600
Asus p8z68-v/gen3
Crucial M4 CT128M4SSD2 2.5" 128GB SSD

My game settings:

Video Settings:
Windowed
1680x1050
2x MSAA
8 General Drawing
4 Background Drawing
Standard Shadow Detail

Graphics:
Only hardware mouse checked
Textures set to high

Thanks!