I have a class wich has a public dynamic Gst.Element.
when in my main programm, I try to connect to a signal (source_setup for example), the compiler says that Gst.Element doesn't have the source_setup signal.
As the object is dynamic, it should work.

Maybe this code example would be better:

// In a first file
public class MyObject : GLib.Object {
	 
	public dynamic Gst.Element playbin;
	public MyObject () {

		playbin = Gst.ElementFactory.make("playbin2", "play");
	}
}


// In a second file
public dynamic Gst.Element playbin2;
int main (string[] args) {
    try {
        Gst.init_check (ref args);
    } catch (Error err) {
        error ("Could not init GStreamer: %s", err.message);
    }
        pipe = new MyObject ();
        pipe.playbin.source_setup.connect (pipe_source_setup); // It doesn't work
        playbin2 = pipe.playbin;
        playbin2.source_setup.connect (pipe_source_setup); // It woks
}