SSRS export to csv on empty no commas

SSRS from Microsoft SQL Server 2012 - 11.0.5058.0 (SP1) when I export a report to CSV with no result, I'm getting header and commas below the headings.   I am expecting a header but I'm not expecting the commas.

 SSRS report Output
 Reference,Portfolio
, ,

 I'm looking for output without commas
 SSRS report Output
Reference,Portfolio

 ------------------------------------------------------------------------------------
 My rsreportserver.config setting is as below
             <Render>
                   <Extension Name="CSV" Type="Microsoft.ReportingServices.Rendering.DataRenderer.CsvReport,Microsoft.ReportingServices.DataRendering">
                         <Configuration>
                               <DeviceInfo>
                                     <Encoding>ASCII</Encoding>
                               </DeviceInfo>
                         </Configuration>
                   </Extension>
             </Render>

With same SSRS rsreportserver.config setting from Microsoft SQL Server 2012 (SP3) (KB3072779) - 11.0.6020.0  I'm getting correct result.