Perhaps too old, but could be useful
This was extracted from http://nerdvittles.com/?tag=piaf
MP3 Playback . Log into your server as root and issue the following commands. If you want to activate the transcription feature, edit the downloaded script and change transcribe=0 to transcribe=1.
chmod +x installmp3stt.sh
Once you have run the installation script, you’ll need to make a couple of adjustments in the FreePBX GUI. Log into FreePBX 2.11 and choose Settings, Voicemail Admin, Settings and make the following changes:
Tags: Droid, GSM, Iphone, voicemail, WAV