Set in configuration fakeLocalDTMF:true
Update sound object in configuration file for the fake DTMF
Here’s how to set it straight through device interface, not through configuration file:
Twilio.Device.setup(token, { sounds: { incoming: 'http://mysite.com/incoming.mp3', outgoing: 'http://mysite.com/outgoing.mp3', dtmf8: 'http://mysite.com/funny_noise.mp3' } }
Dtmf could also be silent.