DataBound ComboBox

Ok, I have a form with a datagridview and a details view next to it for each record. This datagrid is bound to DataBinding1, let's say. In the details pane, one of the controls is a ComboBox that is bound to a customer list / customer ID (DataBinding2). The customer name is the display member, and the customer ID is the value member. The data populates fine, and the ComboBox in the details view changes appropriately as you scroll through records. HOWEVER, when you change the value of the ComboBox, it fails validation, as if it is trying to store the display member (the name, not the numeric ID). I can type a simpe id that exists in the Customer database (i.e., 1), and it will pass validation and store the changes. Any ideas why it is not storing the value member