sip trunk inbound dtmf problem

I just signed up for an configured a sip trunk. Everything seems to work except for inbound DTMF - specifically I am trying to verify my number via google voice dtmf verification, and google does not seem to hear the dtmf tones. Was working fine with my previous provider, ipcomms. Any thoughts?

I used to setup

You may want to send the issue to the support email, voip at freepbx dot com for the service to have a look.

I also don’t quite understand which way you are having dtmf issues. You way inbound? Do you mean you are calling into your system and can’t interact with an IVR or something like that? Or what is the google voice verification doing exactly to try and ‘verify’ dtmf?

Sorry to bump an old post, but did you ever get this figured out, schwark? I’m having the exact same issue with my new sip trunk.

Philippe, when you add a new number for Google Voice ( to forward calls to, they require you verify that number. They use an automated system to do so - they give you a 2 digit code on their website, then their automated system calls your phone number and asks you to punch in the 2 digit code on your phone’s keypad.

I’ve used this exact same phone/FreePBX installation to verify another number with Google Voice that was running on another VOIP provider (Teliax, specifically) but for some reason I can’t get Google Voice to recognize the DTMF tones via the sip trunk.

I just sent a message to SIPSTATION help e-mail to find out if there is something configured incorrectly.

I never did figure it out - finally set my number to forward elsewhere (another sip trunk) to verify on google voice and then switched it back.

Sipstation customer support is really slow - email only - and takes a day or more for then to turn around each turn. So I have not spent the time to go back and forth with them. Not very good support for a support I pay good money for…


I assume someone will be back with you shortly to help isolate and resolve the issue.


I see your issue was back in July 31, 2009. There was a period when we first rolled out the service that we had some glitches in the support. Have you recently had any support issues that are taking you a day or more to get turned around?

I have looked through the email support and responses and from the data I see, it looks like responses are usually sent to customers the same day, and more often then not in less than an hour. The Terms are 24hr business day if you read through the fine print, but the data shows the reality is MUCH better than that.

So if you have been having issues that are not being resolved, PM me with details as I’d be glad to look into it and see what might be going on.