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Voice API

Intermittent WebSocket Disconnections
Symptom Users experience intermittent WebSocket disconnections when util...
What Is An NCCO
Question What is an NCCO and how is it used in Vonage's Voice API? Appli...
How Does Jitter Impact Voice Calls
Jitter refers to the variability in the delay of received packets in a v...
Voice API "Bad Request" Error When Ending Calls Immediately After Creation
Symptom Users receive an error type: 'BAD_REQUEST', error_title: 'Bad Re...
What Is MOS Score In Voice Calls?
Question What Is MOS Score In Voice Calls? Applies To Voice API Answer...
Is there a way to see current active calls on our account?
Question Is there a way to see current active calls on our account? Appl...
How To Make MP3 of Recording From Voice API in Python
Objective How To Make MP3 of Recording From Voice API Applies To Voice ...
How To Enter DTMF Before MP3 Stream Finishes
Applies To Voice API Procedure The bargeIn parameter in NCCOs controls...
Can a user call leg be removed from the voice call recording?
Question The call has 3 users (agent, customer, supervisor). The supervi...
What is a Call UUID?
Question What is a Call UUID?  Why is Vonage asking me for the Call UUID...
Are Manual Timeouts Possible Before NCCO Processing?
Question Can you force a call to ring for an x amount of time before pro...
Does the billing for a call include the time to detect an answering machine? 
Question Do I get charged for the seconds used for machine detection? Ap...
Is there an Additional Cost to record a Voice Call?
Question What is the pricing or cost to record a voice call?  Applies To...
5,000 Milliseconds Timeout on Connection HTTP-Outgoing Error in Log
Question Why do I get this error "5,000 milliseconds timeout on connecti...
How is Vonage Voice data used for AI training?
Question How is Vonage Voice data used for AI training? Applies To Voic...
Which order should Voice API callbacks be received?
Question Why do I receive Voice API event callbacks in the wrong order? ...
What happens if the line is busy when receiving a Voice API call on PSTN endpoint?
Question What happens if the line is busy, engaged, or there is no answe...
Automated Speech Recognition Response Not Valid Term
Question Why is the Speech Input not recognized? Applies To Automated S...
Can I call multiple recipients in one API request?
Question Can I make multiple calls at the same time with Voice API? Appl...
Is a completed event sent to my webhook for every call?
Question Does every call receive a completed event? Applies To Complete...
How can I use Voice API for languages that are not supported?
Question Can I use my own audio files instead of using the Talk action? ...
Do I have to specify the file type in my audio file?
Question Do I have to include .mp3 or .wav in my audio file URL? Applies...
How long is my JSON Web Token valid for?
Question When does my JWT expire? Applies To JSON Web Token Token Expir...
What happens if the audio file download request fails?
Question What happens if the audio file download request fails? Applies ...
What happens if the NCCO download request fails?
Question Will the Voice API retry the NCCO download request if my answer...
API Request failed when trying to Modify an Active Call
Symptom When trying to modify an active call or conversation, I get a 40...
How do I forward additional numbers to an existing application?
Question How can I forward number to existing applications? Applies To ...
Can I use Connect with fallback NCCO with Machine Detection?
Question If a call goes to answer machine, can I hangup and fallback to ...
How can I edit the numbers forwarded to my applications for the Voice API?
Objective Setting up or editing the numbers forwarded to applications fo...
How do I create and manage my applications for the Voice API?
Objective Creating and managing Voice applications. Applies To Voice AP...