How to Configure the Last Message to Play on a VAD Application

The 3CX Voice Application Designer can, among other things, play pre-recorded audio messages. This component configuration seems simple, but it requires special care when playing the last message of an application, otherwise the caller will not hear it.

The Allow Barge-In Property

The “Prompt Playback” component allows defining the property “Allow Barge-In”, which has a default value of “True”. This property indicates whether the message can be interrupted by a DTMF digit in a subsequent menu. With the 3CX IVR implementation, when the value of this property is “True”, the message needs to wait for DTMF digits. Only then is the message played to the user, before the messages of the “Menu” or “User Input” component.

Screenshot of Allow Barge In Property

But if the application does not require DTMF input from the user, for example because we want to play a message and then transfer the call to an operator, the user may not hear the message.
To solve this, we simply need to configure the component with the property set to “False” so we can be absolutely sure that the message will be completely reproduced before proceeding with the execution of the next component, i.e. transferring the call.
This is a common mistake when developing applications with 3CX Voice Application Designer, which can be easily solved.