DTMF problem - fast dtmf

Unanswered Question
Sep 13th, 2010
User Badges:


Some of the IVR systems does not recognize DTMF tone especially when dialing the DTMF tones very fastly. We use call manager and a cisco voice gateway for sending calls to service provider. Is there a way to change the dtmf frequency timers or what should we look/change ?


  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Felipe Garrido Tue, 09/14/2010 - 05:19
User Badges:
  • Cisco Employee,

Is DTMF relay configured on the voice gateway? If so, what's it set to? What type of connection is there to the service provider?


blackswans Wed, 09/15/2010 - 01:53
User Badges:

Yes it is configured;

dtmf-relay h245-alphanumeric

I tried rtp-nte but it didnt worked. DTMF works with h245-alpha but when the users dial dtmf fastly IVRs cannot recognize.

There is a h323 ip connection to the service provider.


Felipe Garrido Wed, 09/15/2010 - 05:31
User Badges:
  • Cisco Employee,

If it's only to a particular IVR then it's an issue with the IVR. There is no way to slow down the DTMF relay process other then having the calling party dial slower. If you see the h245 messages for each digit then the router is doing that it should.


f.kirstein Mon, 12/17/2012 - 09:08
User Badges:

We're having the same problem here.  Verizon Wireless simply does not see keyed responses from Cisco VOIP telephones.  They do recognize keyed input from our old Rolm Phones.  Recently we received a report that a local grade school didn't accept key inputs.  Has a solution been found to this issue?


This Discussion