NullRef/NativeWindow Possible Exception

When creating a new instance of the SyntaxEditor control in code, I will occassionally get the following exception:

System.NullReferenceException: Object reference not set to an instance of an object.
at System.Windows.Forms.UnsafeNativeMethods.CallWindowProc(IntPtr wndProc, IntPtr hWnd, Int32 msg, IntPtr wParam, IntPtr lParam)
at System.Windows.Forms.NativeWindow.DefWndProc(Message& m)
at System.Windows.Forms.Control.DefWndProc(Message& m)
at System.Windows.Forms.Control.WmUpdateUIState(Message& m)
at System.Windows.Forms.Control.WndProc(Message& m)
at System.Windows.Forms.ScrollableControl.WndProc(Message& m)
at System.Windows.Forms.ContainerControl.WndProc(Message& m)
at System.Windows.Forms.ParkingWindow.WndProc(Message& m)
at System.Windows.Forms.ControlNativeWindow.OnMessage(Message& m)
at System.Windows.Forms.ControlNativeWindow.WndProc(Message& m)
at System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)


I can reliably generate this exception in my code (although a blank tester app I can't) and this error always occurs on the following statement:

SyntaxEditor objEditor = new SyntaxEditor();

It may be something I am doing, but can you think of any reason why this exception would occur on the ctor for SE?

Thanks