I dont have a mac to test this, but the Sunburst audio is "Voice" codec, and flip for mac doesnt support this codec.

""""Windows Media Audio Voice 9
20 kbps, 22.05 kHz, mono"""""""""""

""""""""""""""Please note that at this time, Flip4Mac does not support the Windows Media Audio Voice (WMA Voice) codec.""""""""""


You could try this here:

http://www.apple.com/downloads/macosx/video/windowsmediaplayerformacosx.html