DTMF Tones not recognized

I am having a problem where external calls coming in are not passing DTMF tones properly. Due to this problem our automated greeting is not working. I did turn on dtmf logging and do see tones passing sometimes. Does anyone know what the cause of this might be?

Try the following in extensions.conf And see what output is there on CLI.

exten => _X.,1,Read(NumToCall,vm-enter-num-to-call,3)
exten => _X.,n,NoOp(NumToCall=================${NumToCall})

-Urmi

Check your SIP provider which method for sending DTMF digits he is using. You have to set the same for the SIP peer in sip.conf.

You mean under the general context in SIP.conf? Is there anywhere else I can set this? This issue just all of a sudden started a few weeks ago. I have recorded rx streams and you can see/hear tones.

If the streams are inband, you need a low compression codec. Generally only G.711, of the commonly used ones, is at all reliable for in band DTMF. Normally one would avoid it entirely.