AutomaticGraphLayoutControl : Different layout each time

The following code creates a slightly different layout each time it is run. I would expect the same code to always have the exact same layout?

public partial class MainWindow : Window
    {
        public MainWindow()
        {
            var graph = new Graph();

            graph.AddNode("A");
            graph.AddNode("B");
            graph.AddNode("C");
            graph.AddNode("D");
            graph.AddNode("E");
            graph.AddNode("F");
            graph.AddNode("G");
            graph.AddNode("H");
            graph.AddNode("I");
            graph.AddNode("J");
            graph.AddNode("K");
            graph.AddNode("L");
            graph.AddNode("M");

            graph.AddEdge("B", "E");
            graph.AddEdge("C", "E");

            graph.AddEdge("C", "F");
            graph.AddEdge("D", "F");

            graph.AddEdge("B", "G");
            graph.AddEdge("D", "G");

            graph.AddEdge("E", "H");
            graph.AddEdge("F", "H");

            graph.AddEdge("F", "I");
            graph.AddEdge("G", "I");

            graph.AddEdge("I", "J");
            graph.AddEdge("A", "J");

            graph.AddEdge("J", "K");
            graph.AddEdge("B", "K");

            graph.AddEdge("K", "M");
            graph.AddEdge("L", "M");

            InitializeComponent();

            layoutControl.Graph = graph;
        }
    }

Start with the supplied MainWindow reproduction and the AutomaticGraphLayoutControl that receives its graph. Run the example repeatedly and trace where layout positions are assigned or randomized. Done means the same graph produces the same layout on repeated runs, with a regression test if the project has a suitable test entry point.