[Freeswitch-users] voicemail prompts are very quiet

Hi, I've got a basic freeswitch install, just minor tweaks from the default (adding extensions, a gateway and DID). I find the volume of the voicemail prompts are very quiet. Recordings and recorded greetings are great. Is there a way to turn the volume of them up? I had a look through the wiki, but I can't seem to find anything with gain or volume. Maybe I am just looking for the wrong thing. Thanks, Ryan