What I'm trying is so simple, but doesn't work

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Imports Telerik.WinControls.UI

Public Class frmListTest
  Private dtTest As DataTable   

    Private Sub frmListTest_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
            fillDataTable(dtTest)  ' procedure fills the table from an Oracle database procedure

            myDropDownList.DataSource = dtTest

            myDropDownList.ValueMember = "VALUE_MEMBER"
            myDropDownList.DisplayMember = "DISPLAY_MEMBER"

    End Sub

    Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
        myDropDownList.SelectedValue = 6  '  DOES NOT WORK
    End Sub

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dtTemp structure
value_member     display_member
24                         Athletic Operations Building
1                           Camp Randall Stadium
34                         Camp Randall Stadium Misc.
22                         Cr Sports Center [shell] - Womens Hockey
37                         Goodman Diamond All Season Practice
6                           Goodman Softball Complex
23                         Kellner Hall 
2                           Kohl Center
35                         La Bahn Arena
4                           McClain Center

The dropdown list loads ok, but I can't select an item through the SelectedValue property.

What am I doing wrong, or not doing? 

Telerik V 2016.3.913.40

Visual Studio Pro V 14.0.25431.01

Later

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