We have reports of issues with DTMF tones on a snom Meeting Point, particularly when (but not limited to) dialling in to hosted conference facilities.
The user types the access code or conference PIN in correctly, but they are advised that the code is incorrect.
This is because the microphone on the Snom Meeting Point is picking up the DTMF that is played back when the user types a digit. The phone then sends this code twice (once from the actual key press using RFC2833 and once from the microphone using inband DTMF).
There are a couple of settings you can change on the Meeting Point to stop this happening depending on your users preference:
Please Note: The Meeting Point must be on firmware 220.127.116.11 or newer or the settings will not be present in the device
1) DTMF Volume:
Reducing this to a lower setting (1 or 2) may be enough, but setting it 0 will stop the playback of the DTMF tones. This may not be desirable if the customer wants to hear the DTMF being played back to them so they know the key press has definitely registered.
2) DTMF Microphone Delay:
This setting temporarily disables the microphone when a DTMF key is pressed, to stop it from picking up the tone being played back through the speaker. Set this to 1000 so that it delays for 1 second (it is off by default).
The settings do not appear in the web interface so you will need to use the dummy setting URL to save these changes. Simply type either of the following URLs into the web browser on your PC (that is connected to the same network as the Snom):
You need to change ‘ip.addr.of.snom’ to the actual local IP of the Snom Meeting point.
Thats it! Your Meeting Point should now connect to hosted conference rooms without issue.
If you have followed the steps above and are still having issues please email email@example.com.