Hi, I have a scenario where a mobile phone makes a 'normal' call (not SIP/VoIP) into a Freeswitch conference (via a SIP trunk). The dialled number includes DTMF tones to be transmitted after the call is dialled. When sent these DTMF tones can be heard by the mobile phone user. What I want to achieve is that these tones are not audible to the mobile caller. In a previous incarnation of this system the mobile phone dialled into a Twilio hosted conference. In the set-up when the DTMF tones were transmitted the mobile phone user could not hear them. Is it the case that Freeswitch is generating the DTMF tones and if so how can I stop this? If not, what are the possible explanations - e.g. perhaps DTMF tones are played in-band in one scenario versus out-of-band in the other? Any suggestions and thoughts most appreciated. Thanks Mark