DTMF / TouchTone via FRITZ!Box 7530 & Sipgate

We recently ceased our BT landline and ported the number to Sipgate. We are using a FRITZ!Box 7530 as our SIP phone, and have enabled the DECT basestation within so we can continue using our BT DECT handsets we had connected to the landline previously. Incoming and outgoing calls are working perfectly.

However making a couple of calls recently to companies with automated systems, it appears DTMF / TouchTone signals are not being sent when pressing the keypad during a call, resulting in the old "press 1 for this, press 2 for that" menu systems being unusable. Having looked on the Sipgate website we need to set our telephony device (in this case our router) to send DTMF tones via RFC 2833 or Outband. This option is not present in the DTMF list on the FRITZ, the only options being as per the image here: FRITZ!Box 7530 DTMF Options
I've tried every option in that list without success.

So, has anyone successfully got DTMF tones working using a VOIP provider via a FRITZ!Box 7530? Or is the issue purely with the router itself needing a firmware update or similar? It is currently on the very latest firmware for it. If not, any recommendations other than getting some sort of separate VOIP / DECT box or replacing the router for another?

You may have found it but if not there is a Sipgate test number phone number 10020 to test your tones when troubleshooting.

Did you try rebooting the fritz box after the settings were changed in case they don't come into force immediately? When you are pressing buttons on the DECT handset can you hear that handset generating tones? It might be the DECT handset not generating the tones or sending the key presses perhaps.

I'm using a Panasonic KX-TGP600 with Sipgate and that has the specific option to use RFC2833 and that is working. I'd personally recommend a standalone VoIP solution as that way you can swap routers in the future without worrying about will VoIP be supported on that router or work correctly, plus you can restart the VoIP device without affecting your internet connection.

In reply to a post by E300:

You may have found it but if not there is a Sipgate test number phone number 10020 to test your tones when troubleshooting.

Yes indeed, it always shows no tones are sent.

In reply to a post by E300:

Did you try rebooting the fritz box after the settings were changed in case they don't come into force immediately? When you are pressing buttons on the DECT handset can you hear that handset generating tones? It might be the DECT handset not generating the tones or sending the key presses perhaps.

Yes, tried rebooting it. No change. The handset is not generating tones when the keypad is pressed, which is odd as they worked fine and tones were generated and sent when connected to their own basestation and the BT landline.

In reply to a post by E300:

I'm using a Panasonic KX-TGP600 with Sipgate and that has the specific option to use RFC2833 and that is working. I'd personally recommend a standalone VoIP solution as that way you can swap routers in the future without worrying about will VoIP be supported on that router or work correctly, plus you can restart the VoIP device without affecting your internet connection.

Thanks, that looks like a nice setup which I will look into.

I wonder if the DECT handset working in GAP mode is at fault and not sending the right signals to the Fritzbox? Can you hear the tones on the handset?

The option the Fritxbox gives for RTP I think equals RFC2833, as RFC2833 is about sending the tones inside RTP packets as data. The fact it only has this option in conjunction with other options could be the problem as it might be deciding to use a method that doesn't work.

I've just tested on the Panasonic TGP600 and tones work when set as RFC2833 (as recommended by Sipgate so I guess no surprise there) and when set as Inbound, but not when set as SIP INFO, which are the 3 options it has. In theory then the option 'RTP or Inbound' on the Fritzbox should work. For inbound to work though you need to be using u-law or A-law codecs also known as G.711, so if you have option make sure those codecs are given the highest priority to use (better voice quality as well).

Broadband buyer are one of the cheapest places for the TGP 600 (comes with a handset) although currently on back order.

Hope that helps.

I am using a FritzBox 7590 , DTMF tested ok with Sipgate line settings "DTMF Transmission" set to "Automatically" using Gigaset A510 DECT handset.

In reply to a post by E300:

I wonder if the DECT handset working in GAP mode is at fault and not sending the right signals to the Fritzbox? Can you hear the tones on the handset?

No, no tones at all when pressing the keypad. Like I said, odd, as tones worked fine when paired with their original BT basestation. Must be something with the DECT mode the FRITZ is using ? I've had a look through and there aren't that many DECT specific options to play with, however two do stick out that could be worth messing around with: FRITZ!Box 7530 DECT Options

In reply to a post by E300:

Broadband buyer are one of the cheapest places for the TGP 600 (comes with a handset) although currently on back order.

Thanks!

Problem resolved by purchasing a Panasonic KX-TGP600 and handset. Working flawlessly.

In reply to a post by flilot:

Problem resolved by purchasing a Panasonic KX-TGP600 and handset. Working flawlessly.

Good to hear you have tones working now, a shame you needed new kit but at least it also provides you flexibility now to change routers without needing to worry what support they have for VoIP.