AIR25 to AIR28: iOS app crashes when accessing to a Microphone object

Hello,

I'm facing a crash with app compiled with AIR 25 or AIR25 under iOS:

When trying to access a Microphone object, the app crashes and closes.

Hereunder the code:

import flash.media.Microphone;

public var mic:Microphone = Microphone.getMicrophone();

function enregistrer(e:Event):void {

    mic.gain = 60;

    mic.rate = 44;

    mic.setSilenceLevel(0,4000);

    sndByte.clear();

    mic.addEventListener(SampleDataEvent.SAMPLE_DATA,onRecord);

}

private function onRecord(e:SampleDataEvent):void {

    while(e.data.bytesAvailable) {

           var sample:Number = e.data.readFloat();

           sndByte.writeFloat(sample);

    }

}

The crash occurs when pressing the button to which function enregistrer is associated.

Does anybody know how to solve this issue?

Thks in advance