Hi, We moved our current IPBX install from Asterisk to 3CX, using the same SIP provider. Since then, DTMF is not working anymore. From our desk phones, and 3CX soft phones. So, there is probably something wrong in our SIP trunk config, or with the extension config? What should we check ? Something with the codecs ? For now, defaults are G711a/u, which is really common. We also tried unchecking/checking PBX delivers audio on the trunk and extension, but still no result. Any help would be warmly welcome!