An alternative to the built-in WordPress Audio Player (which seems to have some display problems) is the Compact Audio Player. See example at http://studentnews.nisd.net/ortega/?p=54.
The player can embed in a line of text. There is only play and pause.
To use the Compact Audio Player activate its Plugin. From the dashboard sidebar select Plugins > Compact Audio Player and [Activate]. Then—
- Get the URL of the mp3 file. (The file must be mp3 format).
- Enter the shortcode [sc_embed_player fileurl=”URL OF THE MP3 FILE”]
- Paste the shortcode into your post or page
Update your post or page and test it.