I have a Zycoo VOIP gateway. Two locations connected VPN -> IPsec, phones work between locations, but I have a problem with the voip client on the mobile phone. Whether I am in the LAN or am using cellular data, I can register, I can make a call, but only in the local network does my voice work. When disconnecting the WiFi network and connecting to cellular data, despite the fact that I can get through, I can not hear me or the recipient.
I have been sitting for several hours looking for the cause.
Service Port -> sip is enabled.
In addition, the command set in the NAT (because I can not connect without it, being in a different location, despite a VPN connection)
/ ip firewall nat add action = dst-nat chain = dstnat dst-port = 5060 in-interface-list = WAN protocol = udp to-addresses = 192.168.20.200 to-ports = 5060
Where to find the reason for the lack of sound?