parse & decode with SkinValue variable

I've got a problem. I'm making a game and I want my player to change skin when he's entering in the map "monde".

I've got 2 versions of fla files. One for a PC version, and one for android version.

In my “PC version” the code with skinValue is working and it’s not in my “Air for Android version”.

In my PC version I’ve got a player class named player.as :

public function Player(stageRef:Stage, walkRate:Number, targetBuffer:Number){
gotoAndStop(“default”+skinValue);
….
public function startWalking;
gotoAndStop(“walk”+skinValue);
....
public function stopWalking(e:Event):void{
removeEventListener(Event.ENTER_FRAME, walk);
gotoAndStop("default"+skinValue);
In my Engine class (where the game is controled) Engine.as :
 var isMap:Boolean = thisBack == “monde”;
    if (isMap) {
    player.skinValue = “car”;
    }
    else {
    player.skinValue = “”;
    }
    }

My player'got extra frames for that named "walkcar" and "defaultcar". and it’s WORKING GREAT !

But in my AIR version I’ve got this error :

Error #2109: Frame label defaultnull not found in scene defaultnull.

at flash.display::MovieClip/gotoAndStop()

at com.laserdragonuniversity.alpaca::Player()

at com.laserdragonuniversity.alpaca::Engine/createBackground()

at com.laserdragonuniversity.alpaca::Engine/configLoaded()

at flash.events::EventDispatcher/dispatchEventFunction()

at flash.events::EventDispatcher/dispatchEvent()

at flash.net::URLLoader/onComplete()

I search what could be the problem and it seems that JSON is causing this error.

In my PC version I've got, in my engine.as file :

private function linesLoaded(e:Event):void{
            linesData = JSON.decode(speechLoader.data);
...
private function configLoaded(e:Event):void{
            configData = JSON.decode(configLoader.data);

I have to change "decode" by "parse" for my android version and it seems that it's the problem for my Skinvalue ! When it's "parse"..it won't work !

Any idea why ?

Thx !