WP 8.1 XamlGame Create error

Windows Phone
1

i’m trying to navigate from a xaml BlankPage (Page) to xaml GamePage (SwapChainBackgroundPanel)

i change OnLaunched event to go directly on BlankPage

RootFrame = new Frame();
RootFrame.Navigate(typeof(BlankPage));

Window.Current.Content = RootFrame;
Window.Current.Activate();

BlankPage contain a button’s event to create and launch GamePage

var app = App.Current as App;

if (app.GamePage == null) 
    app.GamePage = new GamePage(string.Empty);

Window.Current.Content = app.GamePage;

then when it try to create the game

public GamePage(string launchArguments)
{
     _game = XamlGame<Game1>.Create(launchArguments, Window.Current.CoreWindow, this); // error
}

i got this error

An exception of type ‘SharpDX.SharpDXException’ occurred in SharpDX.DLL but was not handled in user code

Additional information: HRESULT: [0x80070057], Module: [General], ApiCode: [E_INVALIDARG/Invalid Arguments], Message: The parameter is incorrect.

i tried the same strategy on a Windows Store Project and there everything works.

What am I doing wrong?

MonoGame 3.4
MonoGame Windows Phone 8.1 Project