iPhone - Autorotation doesnt work after playing youtube video in other uiviewcontroller

I have a problem with autorotation of a viewcontroller (Inside a tabbarController, this is the only viewcontroller that should autorotate) and this works by setting the shouldAutorotateToInterfaceOrientation:toInterfaceOrientation to just portrait in the AppDelegate and presenting the view that SHOULD autorotate as a modalViewcontroller and

setting shouldAutorotateToIn开发者_如何学运维terfaceOrientation:toInterfaceOrientation in that viewcontroller to YES (=All) This works fine, BUT: after i played a youtube video (in a different viewcontroller) and go back, IT STOPS WORKING! I checked everything, and the hierarchy etc, all seems the same but shouldAutorotateToInterfaceOrientation doesnt get called anymore! All help/suggestions really appriciated!! Thanks!!