plain-purple•4mo ago

How to use dmtf tones

I have enabled them but on IVR it is not working and call is getting ended

13 Replies

Vapi•4mo ago

Vapi's DTMF tool uses in-band tones, which may not work with all IVR systems—especially those expecting out-of-band DTMF. If your IVR supports speech input, try configuring your assistant to say the menu option (e.g., "Sales") instead of sending a DTMF digit. This is the recommended workaround when DTMF tones are not recognized and the call is getting ended.
Example:

{
  "messages": [
    {
      "role": "assistant",
      "content": "Sales"
    }
  ]
}

{
  "messages": [
    {
      "role": "assistant",
      "content": "Sales"
    }
  ]
}

If the IVR does not support speech, you may need to test with different IVRs or monitor for updates as Vapi improves compatibility. Source: - Vapi Default Tools Documentation

⤵️ Mention @Vapi Support Bot for follow-ups 🐥

Duckie•4mo ago

Message marked as helpful by @ghostdragon! 🎉

plain-purpleOP•4mo ago

How to know ivr is out of band dmtf What is the solution for that

Shubham Bajaj•4mo ago

Hey! To help track down this issue, could you share: - The call ID - When exactly this happened (the timestamp) - What response you expected to get - What response you actually got instead
This would really help us figure out what went wrong!

plain-purpleOP•4mo ago

4614cc83-d8f4-4f2c-90c6-9b7ca934ceda @Shubham Bajaj @Shubham Bajaj please look into this @Duckie help me out

Vapi•4mo ago

Vapi currently only supports in-band DTMF tones, which may not work with IVRs expecting out-of-band DTMF. The recommended workaround is to use speech input if the IVR supports it. If not, there is no documented way to send out-of-band DTMF via Vapi at this time. To help us understand your scenario better:
Does your IVR system provide any documentation or technical details about the DTMF method it expects (in-band vs. out-of-band)? This information will help us suggest the most appropriate next steps. For more details, see the Vapi Default Tools Documentation. Source: - Vapi Default Tools Documentation

Shubham Bajaj•4mo ago

Hello @ghostdragon, We are sending the DTMF tones from our side to the IVR navigation on call, but they are not receiving them. This could be an issue with the receiving party. Could you please check if it works for you outside VAPI phone numbers?

plain-purpleOP•4mo ago

outisde vapi number ?

Shubham Bajaj•3mo ago

To verify the functionality of the DTMF tones, make a phone call using a different number (such as your own phone number) to the customer's phone number. When you press the digit, does it work? Can the customer's phone number receive the DTMF tones? If yes, try sending the DTMF tones using a Twilio phone number instead of the phone number provided by VAPI. If this doesn't resolve the issue, please share the call ID.

plain-purpleOP•3mo ago

I will let you know i have to get twillio number first

Shubham Bajaj•3mo ago

hey a gentle reminder to continue this thread.

plain-purpleOP•3mo ago

I will let you know

Shubham Bajaj•3mo ago

Hey until then I am marking this ticket as solved.

How to use dmtf tones

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