DTMF works intermittently on Outbound calls with E1

[techToddler]

Hello Folks,

Need your help with some weird problem. 

Setup is like below,

IPPhone -- CUCM ---SIP trunk ----Gateway ---E1---Serivce Provider.

We have an issue saying the DTMF is intermittently working on outbound calls. Calling a certain gets connected to a IVR and pressing a access code doesn't work at times. Same location and same phone. 

Could someone help me how to trouble shoot this problem .

Regards

Sanjay

[Deepak Mehta]

Hi Sanjay,

If it is intermittent then your SIP dial-peer might be missing DTMF config.This is the first thing you can check.

In general we should use both SIP-KPML and RTP NTE so that either one can be used by GW without needing an MTP.

What is phone model and CUCM version .You may want to run debug voip rtp session named-event and debug ccsip messages to check what DTMF types is being sent to the provider?

[techToddler]

Hello Deepak,

Thank you for your suggestions.

Will check and let you know. Thanks

Regards

Sanjay.

[Richard Simmons]

I had a similar issue to this a while ago, some outbound calls were hitting the default dial-peer, once i got all calls to use the correct dial-peer then it resolved my issue.

You can use either show voice call summary or show voice call status (can't remember which one it is) to identity easily identify which dial-peer is being used on the active call.

Regards,

Richard