DTMF and Voice message at same time

Hi Everyone,

I want to build a IVR which accepts DTMF and play a voice message at the same time without interrupting both DTMF accepting and playing voice message. I have tried Background() and not successful.

Can anyone help me?

Thank you

Playing sound during DTMF can produce false digits, as a result of echoes and talk-off. Also the echoes reduce the signal to noise ratio for the tone detection, causing digits to be missed. Consequently, it is normal to suppress the background as soon as a digit is detected.

Try setting your dtmfmode=rfc2833 for out of band dtmf. It should help by not putting the dtmf in the audio stream. Make sure your codec is ulaw or alaw.

voip-info.org/wiki/view/Aste … p+dtmfmode

According to the doc, the codec only matters if you’re trying to use dtmfmode=inband.

That’s only going to help if it is VoIP end to end. If these calls are coming in over the PSTN, the echo will happen before the tone decoder.

The initial questions says nothing about VoIP.


Thanks for your replies.
I’m passing the DTMF from an Android App over GSM, not SIP. I have an IVR which accepts the DTMF in PSTN Network.
I need to play a Welcome voice message along with accepting DTMF.

Any idea ?

Thank you

Use AMI and monitor the DTMF events. Expect near end cross talk.

Good point, I had only considered the IVR from a SIP phone, or behind a proxy.

Turn on the DTMF logging (logger set level DTMF on), and use the Read() application.