The issue can be reproduced with the .40 version of the assemblies and in a scenario in which the grid is added as a RadMenuHostItem to the Items collection of a drop-down button.

Workaround:  set the BindingContext of the grid to equal that of the form: 
public Form1()
{
            InitializeComponent();

            radGridView1.BindingContext = this.BindingContext;
}