Calling short code number (support services) with Asterisk GSM Gateway

Question

In our company we have configured VOIP GSM gateway with Astersik. We can call any number with this gateway but the only problem we face is when we call some support service. When a support service says please pres 1 for this service, pres 2 for this service... At this moment we are not able to press these numbers ! Any idea

Answer 1

That is a DTMF problem. How is your gateway connected to Asterisk? Via SIP? I think there are two things your should look: 1. In your GSM device config menu, see the DTMF options and check if something looks wrong. 2. Check in your Asterisk PBX what dtmf preferences you have. Look at the following:

dtmfmode = inband|info|rfc2833 (global setting). Default rfc2833.
relaxdtmf = yes|no: Default no.

It is important that your Gatweay settings match your sip.conf settings