You can convert pre-recorded audio files for use as auto-attendant prompts.
It can take up to 5 minutes before the system begins using a newly uploaded file.
If a system administrator records a new prompt from their phone, the pre-recorded file is deleted.
You can also use pre-recorded files for user mailboxes. See Using pre-recorded auto-attendant prompts.
The source WAV file must have the following properties:
8KHz Mono
16-bit PCM Uncompressed