Your sound files are linked (linked object: An object that is created in a source file and inserted into a destination file, while maintaining a connection between the two files. The linked object in the destination file can be updated when the source file is updated.) and not embedded (embedded object: Information (object) contained in a source file and inserted into a destination file. Once embedded, the object becomes part of the destination file. Changes you make to the embedded object are reflected in the destination file.), and the sound files need to be sent along with your presentation. Copy the sound files into the folder that contains your presentation, and then use the Package for CD feature to update the links and bundle the associated files.