PDF Saving in C# Application

I have created a word document which contain a table 
This table contains an image which i hyper-linked it with a link to a sound
It works fine in word
But when i am trying to save it in PDF, the hyperlink doesn't work

I use the following built-in Method

docObject.ExportAsFixedFormat(outputFileName, WdExportFormat.wdExportFormatPDF, false, WdExportOptimizeFor.wdExportOptimizeForOnScreen,
                    WdExportRange.wdExportAllDocument, 1, 1, WdExportItem.wdExportDocumentContent, true, true,
                    WdExportCreateBookmarks.wdExportCreateHeadingBookmarks, true, true, false, ref oMissingReference);
           
What is wrong with me ??

Thanks