[Help] DTMF not work

Asterisk Asterisk Support
1

Hi,

DTMF is working fine interfacing with Asterisk Voice Mail. The problem is when I dial 1-800 number and enter some numbers, it doesn’t get recognized by 1-800’s IVR system. I switched dtmf mode to “info” from “rfc2833” and the result is still the same.

Can someone give me a direction on how to debug this problem? Attached below is what printed on “asterisk -rv” with “sip debug”.

Thanks

Sip read:
INFO sip:18008693557@192.168.15.200 SIP/2.0
Via: SIP/2.0/UDP 192.168.15.107:8491
Max-Forwards: 70
From: “Jamie C” sip:101@192.168.15.200;tag=78ea3d69aa424cacaadf479fed4af68b;epid=acb19b5a43
To: sip:18008693557@192.168.15.200;tag=as57586224
Call-ID: b7f0c3244f5549138b21e6748a81ca55
CSeq: 3 INFO
Contact: sip:192.168.15.107:8491
User-Agent: RTC/1.3
Content-Type: application/dtmf-relay
Content-Length: 21

Signal=1
Duration=160
11 headers, 2 lines
Receiving DTMF!

  • DTMF received: '1’
    Transmitting (no NAT):
    SIP/2.0 200 OK
    Via: SIP/2.0/UDP 192.168.15.107:8491
    From: “Jamie C” sip:101@192.168.15.200;tag=78ea3d69aa424cacaadf479fed4af68b;epid=acb19b5a43
    To: sip:18008693557@192.168.15.200;tag=as57586224
    Call-ID: b7f0c3244f5549138b21e6748a81ca55
    CSeq: 3 INFO
    User-Agent: Asterisk PBX
    Allow: INVITE, ACK, CANCEL, OPTIONS, BYE, REFER
    Contact: sip:18008693557@192.168.15.200
    Content-Length: 0
    [/b]
2

To start with, you’ll need to find out what type of DTMF your ITSP uses - and then use the same. As well as “info” and “rfc2833”, there’s “inband”.

3

I had simliar problems with DTMF when I upgraded to v1.2. I figured out thatI had to put the following in either each specific SIP extension or in the [general] section of sip.conf:

relaxdtmf=yes
dtmfmode=inband

However, just today I upgrade to the latest branch release of Asterisk 1.2.x and my outgoing DTMF stopped working. I went in and commented out these lines and voila it’s working again.