Mind the DTMF mixed quality BADLY affects your communications. I have a real story for you; I'm calling one of my banks, they Rep is transferring me to a robot to enter my pin #... I'm entering it, and the robot can't understand the pin. The robot says to enter again... after 3 tries it gives up. ...., and it does not understand your commands due to the line in not DTMF. You must troubleshoot DTMF problems with your VoIP connection through route-test.com. They offer a free testing credits. You can find the solution quickly. #VoIP