This comes from a post in the PBX in a Flash forum by user matt91 and was slightly edited, but will probably work on most FreePBX installations of recent vintage. Note that at one time you could get 30 seconds of voice transcribed but now it is only 15, but that still may be enough to help you quickly decide if you want to listen to the full message. If you are not running PBX in a Flash then open the batch file in a text viewer before you run it and make sure it’s not going to do something you don’t want it to do, and run it at your own risk.

1. Log into your server via SSH as root and…

cd /root
wget -N http://www.deltaend.net/pbx/installmp3stt.sh
chmod 0755 installmp3stt.sh
./installmp3stt.sh

2. In FreePBX, choose Settings -> Voicemail Admin -> Settings, make the following changes, then click Submit and Reload FreePBX.

format -> wav
mailcmd -> /usr/sbin/sendmailmp3

3. Leave yourself a voicemail and you should see the first 15 seconds of the voicemail transcribed for you.