Hello I cis questions about the generation of Ring Back Tone. I am using the 3CX server on the remote environment, but I am in trouble Ring Back Tone is inaudible. Environment are as follows. OS: Windows2012Server, firewall is off Terminal: 3cx client, Yealink fixed telephone Line: VOIP trunk, IP phones line of Japan 3cx is connected through a tunnel Yealink was no use or "Enabled" and "180 Ring Workaround", even if you set any of the "Disabled". Will there a way to generate a Ring Back Tone?