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Note: The recorded prompt must be a WAV file. Also, ensure the prompt file is recorded in monophonic not stereophonic as it will be played and listened to over the telephone, which is a monaural system and is unable to play stereo recordings.
The correct format should be:
Ensure 'Recording Channels' is set to 'Mono'.
Select 'Default Sample Rate' to '8000hz'.
Select the 'Default Sample Format' of '16 bit'(8 bit is supported)
Set 'Header' to 'WAV (Microsoft)'
Set 'Encoding' to ‘PCM'
The WAV file should not exceed 3MB
To create a new prompt version:
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