I fill a list box (Mere Morals) this way:

Models oModels = (Models)this.RegisterBizObj(new Models());
// Get a DataSet containing all makes
DataSet dsGetModels = oModels.GetModels(MmDropDownList1.SelectedItem.Text);
// Persist the DataSet to the Session object
Session["dsGetModels"] = dsGetModels;

MmDropDownList2.DataSource = dsGetModels;
MmDropDownList2.DataTextField = "pi_model";
MmDropDownList2.DataValueField = "pi_applpg";
MmDropDownList2.DataBind() ;

I have unique displayed Models pi_model, and redundant Pages pi_applpg. (This is a printed catalog). Many different models will show on the same page.

When I fill the list box, and move to a new record SOMETIMES the SelectedIndexChanged doesn't fire, other times it does. More research shows that the "page" is the same. If I see data in the list as 1,2,3,....15. #1 is initially selected. User will pick #3, but #1 stays in the control. Why? Is it the DataValue is the same? (same page ?)

__Stephen