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as the title suggest, I'm having problems with my UIScrollview, which movements get jerky after I play a CABasicAnimation. The animation flips the UI elements on the screen (up to 10) around while fading them out. To do this, I use the code below:

-(void)flipLayers:(UIView *)view {

    CGFloat subviewX = ((1/view.frame.size.width)*(view.frame.origin.x+200));
    CGFloat subviewY = 0.5;
    [self setAnchorPoint:CGPointMake(-subviewX, subviewY) forView:view];

    CALayer *layer = view.layer;
    layer.shouldRasterize = YES;

    CATransform3D aTransform = CATransform3DIdentity;
    CGFloat zDistance = 2000;
    aTransform.m34 = 1.0 / -zDistance;  
    scrollView.layer.sublayerTransform = aTransform;

    CATransform3D bTransform = CATransform3DIdentity;

    CABasicAnimation *rotateAnim = [CABasicAnimation animationWithKeyPath:@"transform"];

    rotateAnim.fromValue= [NSValue valueWithCATransform3D:bTransform];
    bTransform = CATransform3DRotate(aTransform, -M_PI_2, 0, 1, 0);;
    rotateAnim.duration=0.2;
    rotateAnim.timingFunction = [CAMediaTimingFunction functionWithName: kCAMediaTimingFunctionEaseIn];
    rotateAnim.toValue=[NSValue valueWithCATransform3D:bTransform];
    layer.transform = bTransform;
    rotateAnim.removedOnCompletion = YES;
    [layer addAnimation:rotateAnim forKey:nil];

    CABasicAnimation *fadeAnim = [CABasicAnimation animationWithKeyPath:@"opacity"];
    fadeAnim.duration = 0.12;
    fadeAnim.removedOnCompletion = YES;
    fadeAnim.beginTime = CACurrentMediaTime() + 0.08;
    fadeAnim.fromValue = [NSNumber numberWithFloat:1.0];
    fadeAnim.toValue = [NSNumber numberWithFloat:0.0];
    [layer addAnimation:fadeAnim forKey:nil];

 }

To restore the UI elements original position in a similar manner, I use this code

-(void)flipLayersBackwards:(UIView *)view  {

    CALayer *layer = view.layer;

    CATransform3D aTransform = CATransform3DIdentity;
    CGFloat zDistance = 2000;
    aTransform.m34 = 1.0 / -zDistance;  
    scrollView.layer.sublayerTransform = aTransform;

    CATransform3D bTransform = CATransform3DIdentity;

    CABasicAnimation *rotateAnim = [CABasicAnimation animationWithKeyPath:@"transform"];
    rotateAnim.fromValue= [NSValue valueWithCATransform3D:CATransform3DMakeRotation(M_PI_2, 0, 1, 0)];
    bTransform = CATransform3DRotate(aTransform, 0, 0, 1, 0);;
    rotateAnim.duration=0.2;
    rotateAnim.removedOnCompletion = YES;
    rotateAnim.toValue=[NSValue valueWithCATransform3D:bTransform];
    rotateAnim.timingFunction = [CAMediaTimingFunction functionWithName: kCAMediaTimingFunctionEaseOut];
    layer.transform = bTransform;
    [layer addAnimation:rotateAnim forKey:@"rotateAnim"];

    CABasicAnimation *fadeAnim = [CABasicAnimation animationWithKeyPath:@"opacity"];
    fadeAnim.duration = 0.064;
    fadeAnim.removedOnCompletion = YES;
    fadeAnim.beginTime = CACurrentMediaTime() + 0.02;
    fadeAnim.fromValue = [NSNumber numberWithFloat:0.0];
    fadeAnim.toValue = [NSNumber numberWithFloat:1.0];
    [layer addAnimation:fadeAnim forKey:nil];

    layer.shouldRasterize = NO;

}

The more times the animation is used, the jerkier the scrollview's movement get. Does anyone have an idea what could be causing this? Any help on how to fix this would be greatly appreciated. Thanks in advance :)

EDIT: I have found that the perspective transform is the cause of the choppiness, but I have no idea what to do about it

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