Cannot insert an MP3 sound file in Impress

Message says ‘The format of the selected file is not supported’ every time. I’m using Windows 8.2 with Libre Office 4.3.6.2. The file is originally from Microsoft Powerpoint . ppt and the sound files I’m trying to insert are MP3. How do I insert my sound files? Do I need a different format?

Click on the menu “Insert : Audio or Video…”, then a File Dialog pops up where you can browse to your MP3 file. Select the MP3 file and then click on the “Open” button to insert it into your Impress slide.