Issues with IVR and DTMS


My PBX Spec:

  • FreePBX
  • DIGUIM AEX410 Analog Card
  • DIGUIM VPMADT032 - Echo Cancellation Module
  • 3 PSTN Lines

Sometimes, many times, the DTMFS received are not good, sometimes extra digit, sometimes its total different digit.
i am in steps of tweaking it so it will work correct, but really I no longer know what steps i should do.

before doing the steps below, i didn’t receive any DTMF at all.

  1. I followed all Diguim Manuals and this one manually
  2. i have used FXOTUNE according to the link and also detuned the ECHO Cancellation module like they said.
  3. I have enabled DTMFS LOG in FreePBX(It doesnt give a good output)
  4. I cant understand if this happing on all lines or a specific lines. from my tests it sometimes happans on random
  5. Sometimes the IVR Changes, I cant explain this behave, once i see the problem, its sometimes repeating, then i go to IVR Manually, refresh everything, then it works again like it should.

What other steps should i Do then?

  1. Remove the Echo Cancellation Module?
  2. Maby Increase/Decrease the DHADI GAIN?

Yea, don’t push the gains up too much…

Are your lines noisy by any chance?

Do you have


Enabled in chan_dahdi.conf?