Unanswered Question
Sep 22nd, 2008
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we have the following problem:

in general DTMF works fine with calls that come from an outside SIP trunk to internal phones (hardware MTP is used for this). However, for calls from outside that go to CTI ports on IPCC (IVR ports) the DTMF does not work. What could be wrong?



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Overall Rating: 5 (1 ratings)
jbayuka Fri, 09/26/2008 - 13:08
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Can you please send a "show tech-support" from the gateway that is not sending all the DTMF digits? Also, is this a new install/configuration or a new issue on and existing installation? What has changed recently? Can you give more details on the complete call flow?

gogasca Sun, 09/28/2008 - 22:27
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Afaik CTI doesnt recognize the RFC2833 and should invoke a Transcoder.

Currently if CTI needs to talk to a SIP endpoint and if this only supports 2833, a MTP will always be required even if the app does media bridging to a endpoint that suppports 2833 or if the app supports 2833

Try to use SIP Notify OOB configure that in IOS if using IPIP and also in SIP Trunk configure accept Unsolicted Notify under SIP trunk profile.


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