Hi,

I have an freeswitch system running which accepts incoming calls and requests a pincode for people to identify themselves to the system. I am getting an increasing number of issues where the dtmf tones being received appear to get doubled up. So I enter 1234 on my telephone keypad and 11223344 appears to be received in the buffer when calling getDigits. This doesn’t happen all the time but often enough to be a problem. All the calls in to my system are forwarded on to me directly via SIP from a major UK telecoms provider that terminates numbers for us.

Can anyone suggest what dtmf settings I may have got wrong that would cause this phenomenon or any suggestions how I can go about fixing it?

I’m using …

<action application="start_dtmf" />

In my dialplan. And these settings in my SIP profile:

<param name="dtmf-duration" value="100"/>

<param name="dtmf-type" value="rfc2833"/>

Any help much appreciated.

Many thanks

Andy