Sound resume issue

Hi everyone!

I have some issue with resuming sound on iOS devices. If I block device while playing my app then unblock it in a short time everything is fine and all sounds in my app resume, but if I wait some minutes while device is blocked, then unblock it and  now the sounds doesn`t play, or start to play later after some time left.

To stop the app I use this:

private function deactivate(e:flash.events.Event):void

                    {

       flash.system.System.pause();

        Starling.current.stop();

                    }

private function activate(e:flash.events.Event):void

                    {

                                   flash.system.System.resume();

                                   Starling.current.start();

                    }

I also try this to hide only the sound:

private function deactivate(e:flash.events.Event):void

  {

     SoundMixer.soundTransform = new SoundTransform(0);

  }

  private function activate(e:flash.events.Event):void

  {

       SoundMixer.soundTransform = new SoundTransform(1);

  }

but it still don`t work (( Hope I could explain my problem! any ideas or advices?

Thanks in advice!