This is 3rd situation where something is wrong. After reboot TeamSpeak3 server, everything is ok for a while ...

http://www.gametracker.com/server_info/ts.lowping.eu:9987/

I dont want to all the time reset mine ts3 server..

cat /home/ts/teamspeak3/query_ip_whitelist.txt
85.234.144.159
127.0.0.1
77.79.246.241
86.21.251.20
94.23.235.222
208.167.241.190
208.167.241.185
208.167.241.186
208.167.241.183
208.167.241.189
108.61.78.147
108.61.78.148
108.61.78.149
108.61.78.150

2015-02-08 18:18:56.657716|INFO |VirtualServerBase| 1| client disconnected 'Gimbus'(id:410) reason 'reasonmsg=leaving'
2015-02-08 18:20:00.874359|INFO |VirtualServer | 1| query client connected 'Unknown from 108.61.78.149:39442'(id:18)
2015-02-08 18:20:00.976500|INFO |VirtualServerBase| 1| query client disconnected 'GameTracker'(id:18) reason 'reasonmsg=connection lost'
2015-02-08 18:20:03.350147|INFO |VirtualServer | 1| query client connected 'Unknown from 108.61.78.149:50315'(id:18)
2015-02-08 18:20:03.432539|INFO |VirtualServerBase| 1| query client disconnected 'GameTracker'(id:18) reason 'reasonmsg=connection lost'

What is it mean ?

If you're able to hit Update Scanning Parameters to get it back online, but then it goes offline shortly after, this is indicative that you are blocking one or more of the scanner IPs. Meaning, an actual firewall.