Hi, we want to use this service https://www.messagebird.com/en/voice-messaging for critical alarms i

Hi there,

Unfortunately, we don't have any successful implementations of Text-to-Speech or Call-Notifications. We don't really recommend this way to be notified as if something went wrong you will receive hundreds of calls which could be very expensive. But if you want to implement such a feature we recommend to use an external API service (e.g. https://www.messagebird.com/de-de/text-to-speech) where you can send an HTTP request to. To send an HTTP request in case of a notification just enable the "Execute HTTP Action" option in any notification (Setup > Account Settings > Notifications). There you are able to add POST-Data which will be parsed by the API of the service. For detailed information contact the API-Provider or read the online documentation.

Best regards.