Why do all users have a local IP on a Teamspeak server?

Question

linux

Hello, I want to describe a problem on my home Teamspeak server.
The fact is that clients do not see their external IP in the information, only 192.168.1.1 (given the screen below)
Router - OpenWRT - 192.168.1.1
Server - Ubuntu 14.04 - 192.168.1.5
Ports forwarded, costs DDNS to Afraid.org
The server is located behind the firewall of the router and does not have its own.
If more detailed information is needed for a solution, I will write.
Screenshot:

Answer 1

Show how ports were forwarded, if through gui, then it should be so. You will need to edit iptables