Full-Screen mode of app extremely slow

[Galbata]

Hi.

I built an AS3 app that I export as AIR-app as installer to be run in full-screen. So I set it to:
stage.displayState = StageDisplayState.FULL_SCREEN_INTERACTIVE;
stage.scaleMode = StageScaleMode.SHOW_ALL;

Everything works, except that if in full-screen mode, the App is extremely slow. It's some sort of gallery, where a new image slides in and an old one slides out. And that animation is really choppy, but only in full-screen. In window-mode, even if it is actually the same size, it's very very slow.

I already tried a lot to improve the performance. Use JPGs whenever possible, keep PNGs files tiny (of those only a few small ones are needed), have all objects visibility set to false if they're currently faded out, and so on.

Anyone got any advice?

Why is the app running fluently even on slower computers in windowed mode, but is so slow in full screen even on faster machines?

Thanks for any help.

[Galbata]

Problem solved. Setting up a stage.fullScreenSourceRect first and THEN scaling it to fullscreen solved any problem.