Unthrottle question

[Crowmeister]

I'm currently playing GoW:GoS and when I hold the unthrottle button it (as expected) speeds up the game with about 200% which is great. But after 1-2 seconds the opposite happens and the game becomes really slow, slower than 100%.
Even though the speed-o-meter in the top-right says the game runs at ~200%.

So it speeds up fine for 1-2 seconds, speed-o-meter confirms it running at ~200% speed, then the game slows to (I'm guessing) about 50-70% speed EVEN THOUGH the speed-o-meter still says it's at ~200%.

What am I doing wrong? I've tried quite a few options but boy does this emulator have many options and speedhacks.

Currently I have VSync disabled, Frameskipping off, Auto frameskip off, Prevent FPS from exceeding 60FPS ON, OpenGL, Buffered Rendering.