To reproduce:

- Open the Excel-like filtering example in the demo application and sort the second column. 

- The sort icon is over the text. 

Workaround:

private void RadGridView1_SortChanged(object sender, Telerik.WinControls.UI.GridViewCollectionChangedEventArgs e)
{
    this.radGridView1.TableElement.Update(GridUINotifyAction.StateChanged);
}