For IVRs and Queues, sound files have the following format:

Greetings: 'greeting-$NAME.gsm'

Queue greetings: 'queue-greeting-$NAME.gsm'

Agent announce: 'agent-announce-$NAME.gsm'

Periodic announce: 'periodic-announce-$NAME.gsm'

Queue Callback Agent and Caller announce:'qc-announce-$NAME.gsm'

GSM files can later be converted to other formats using PBXware.