We use Amazon Polly on our end. We create recordings (with SSML alterations) for prompts that are static, but use Amazon Polly on-the-fly for any variables. Our Play Audio segments are constantly flipping between pre-recorded prompts and real time variables, which is seamless to the customer.
Genesys has some nice functions that you can wrap around the returned variables (date, currency, etc) in order to make things sound more natural. Our experience with Amazon Polly has been overwhelmingly positive.
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Cory King
IT Lead
IGS Energy
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