WPF Ivalueconverter Not firing

Question

Here is my xaml below. The DisplayUnitConverter is not firing when I click the radio buttons.Can someone assist me to see what I am doing wrong?

 

<Window x:Class="DisplayUnitClient.MainWindow"

xmlns:dx="http://schemas.devexpress.com/winfx/2008/xaml/core"

xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"

xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"

xmlns:d="http://schemas.microsoft.com/expression/blend/2008"

xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"

xmlns:dxe="http://schemas.devexpress.com/winfx/2008/xaml/editors"

xmlns:dxn="http://schemas.devexpress.com/winfx/2008/xaml/navbar"

xmlns:dxlc="http://schemas.devexpress.com/winfx/2008/xaml/layoutcontrol"

xmlns:DisplayUnitClient ="clr-namespace:DisplayUnitClient"

mc:Ignorable="d"

Title="MainWindow" Height="350" Width="525">

<Window.Resources>

<DisplayUnitClient:DisplayUnitConverter x:Key="DisplayUnitConverter" />

</Window.Resources>

<Grid>

<dxe:SpinEdit x:Name="spinEditMaxHatchSpeed" Height="{Binding ActualHeight, ElementName=label}" AllowDefaultButton="False" Value="{Binding MaxHatchSpeed, ElementName=groupBoxDisplaySettings, Converter={StaticResource DisplayUnitConverter}, Mode=TwoWay}" Margin="0,0,0,285">

<dxe:ButtonInfo IsLeft="True" Content="&lt;" Command="{Binding SpinDownCommand, RelativeSource={RelativeSource AncestorType={x:Type dxe:SpinEdit}, Mode=FindAncestor}}"/>

<dxe:ButtonInfo Content="&gt;" Command="{Binding SpinUpCommand, RelativeSource={RelativeSource AncestorType={x:Type dxe:SpinEdit}, Mode=FindAncestor}}"/>

</dxe:SpinEdit>

<GroupBox x:Name="groupBoxDisplaySettings" Header="Display Units" HorizontalAlignment="Stretch" VerticalAlignment="Top" FontSize="16" Margin="0,39,10,0">

<StackPanel HorizontalAlignment="Left" VerticalAlignment="Center" Orientation="Vertical" Width="349" >

<Label Content="Max Hatch Speed:" />

<RadioButton Margin="0,0,20,0" Content="Millimeters" Name="MillimeterDisplayUnitButton" GroupName="DisplayUnits" Click="DisplayUnitMode_Clicked" Tag="0"/>

<RadioButton Content="Inches" Name="InchesDisplayUnitButton" GroupName="DisplayUnits" Click="DisplayUnitMode_Clicked" Tag="1" />

</StackPanel>

</GroupBox>

</Grid>

</Window>