I am using combox webform ajaxtoolkit. When typing the searching text in the textbox, the dropdownlist will come down as well. However, I found the results matching the searching text has been scrolled up passing the visible window. I have to use mouse to scroll up in order to see the matching result. For example, if I search "sa.." the current dropdownlist window will show item starting from 'sp...", I need to scroll up to see results for 'sa...'. It's so weird, all the items matching 'sa...'should be in the current dropdownlist. Anyone has the same problem before?
<ajaxToolkit:ComboBox ID="ddlCustomerName" runat="server"
AutoPostBack="True"
DropDownStyle="DropDownList"
AutoCompleteMode ="SuggestAppend"
CaseSensitive="False"
ItemInsertLocation = "Append"
RenderMode="Inline" ListItemHoverCssClass="comboBoxItemHover"
AppendDataBoundItems="True"></ajaxToolkit:ComboBox>