Binding Textblock with Property having text "Audit" displays text "Audi"

I am binding a TextBLock with a string Property but whenever this Property contains the text "Audit", the actual text displayed on the UI is "Audi". For any other scenario, this works fine.

I am using .Net 4.0 and OS is win XP.

I am not sure if this is a bug but I can't get rid of this. If it is a bug, where do I report WPF bugs? Can anyone else also reproduce this issue? If yes, is there a workaround?

Edit: The Binding for the textblock is:

<TextBlock Padding="0,5,5,5" TextWrapping="Wrap" Text="{Binding TaskRoleMapping}" FontWeight="Bold" Foreground="White" FontFamily="Segoe UI" Margin="3,0,0,0" VerticalAlignment="Center"/>

I am sure it's not a problem with the textlength as much bigger text gets displayed alright.

Edit: The TextBlock is contained in a StackPanel

<StackPanel Height="40" Orientation="Horizontal" VerticalAlignment="Top" HorizontalAlignment="Left" Width="Auto">            
        <ContentControl Content="ContentControl" Template="{DynamicResource vector_Summary}" Height="16"/>
        <TextBlock Padding="5,5,0,5" Height="28" 
                   Text="{Binding Path=[LABEL.MAIN.HEADER], Source={x:Static Util:Util.labelDictionary}}" 
                   FontFamily="Segoe UI" FontSize="12" 
                   Foreground="#FFFFFF" Margin="1,7,0,0" VerticalAlignment="Top" HorizontalAlignment="Left" Width="Auto"/>
        <TextBlock Padding="0,5,5,5" TextWrapping="Wrap" Text="{Binding TaskRoleMapping}" FontWeight="Bold" Foreground="White" FontFamily="Arial" Margin="3,0,0,0" VerticalAlignment="Center"/>            
</StackPanel>

Solution

I like Kent Boogaart's comment/points. Basically 't' char is being cut off/out from the view. So change the font size to smaller, or remove "Bold" or introduce min size of the TextBlock, or it's parent and 't' in "Audi" will magically appear