unity bug when setting quality?

I have a client / server game. When a client connects to the server, then a model is also placed in the server world. Currently the server renders the entire world too. The models are moving by applying a force. So far everything works fine until i execute the ‘executable’ file of the server.

So in the unity editor i went to File → Build Settings → Build and i executed the file thats created. When opened it displays a form in which i can specify the quality of the game varying from “Fastest” to “Fantastic”.

When i choose one of the first three “Fastest, Fast or Simple” then for some reason the game runs 10x to fast. I have the feeling the physics simulation is the problem, since i’m using that to move the objects forward.

Here’s a sample video of my problem:
http://www.screencast.com/t/AV5zOzJMS

Is this a bug…??

physics don’t use the framerate, they don’t care about it.

that it runs up to 10 times as fast framerate wise is very well possible due to the delta in rendering code etc.
if you were on pro you would not run the server with graphics at all but start it through a batch file / command line and add -batchmode to run it in headless which will run much faster / preserving much more computer resources

And you would likely want to use Application.targetFramerate

Thats what i’m worrying about, when i eventually run it as batchmode.

So i guess i can use targetFramerate to solve my problem. But i still don’t see how my model moves 10x as fast when its movement is based on physics (AddForce). I don’t see how faster rendering is affecting that.