Sustained ~90FPS plus slowdown

[centry]

This is apparently only happening when playing in the Shiva Editor (WinXP). In the bottom right of my screen I keep a hud item to keep track of FPS, Draw Calls, and Triangles. Fairly often, when I play the game in the editor, it shows the game as running at around 90 FPS (80-100 range) and the game similarly runs slowly.

Since my game is very simple and usually is only around 12 draw calls and 200 triangles, I get the feeling there is some mathematical error when Shiva is running that basically makes the game run at a time ratio of (90 / 60 = 1.5) times slower than normal to create the supposed 90 FPS. This doesn't always happen, but when it does, usually even restarting the computer won't fix it. It'll run this way for a while, and other times it works fine. I haven't noticed this behavior when testing it on android or palm or when running it as an executable in windows.

It's sort of an odd issue and may be hard to track so I'm wondering if anyone else has had a similar problem?