[Freeswitch-users] how to play a file to recipient

Hi All, I want to play a message to recipient to advise them what line call came in, in Avaya world this is known as Whisper / VDN of Origin Announcement. what I want to achieve is when call hits the Gateway its setup to route call to an extension, when extension answers the call they hear a wav file or a message via (Freeswitch SAY command) saying "customer service" or "Return" etc... thanks in advance, kaleem