Sync does not try the correct port

[Ragnar]

Hello,

using Sysinternals procmon.exe i see that my BTSync Clients are not trying to connect to the correct Internet port and am wondering why.

Client1 (LabServer at my company) ListeningPort=64881, UPNP:yes, FolderConfig: use tracker, Search DHT

no Portforwarding and i dont think UPNP is enabled at my company

Client2 (laptop at Home) ListeningPort=44253, UPNP:yes, FolderConfig: use tracker, Search DHT

On my Arcor Easybox A 300 at home i have configured Portforwarding 44253 to the IP of my laptop (192.168.15.15) and have enabled UPNP

So i expected to see the LabServer connect to 192.168.15.15(MyLaptopLocalIP):44253 but it seems only to connect to random Ports.

BTSync.exe - UDP Send - 10.1.2.3(MyServerLocalIP):64881 -> 22.33.44.55(MyHomeInternetIp):44298

BTSync.exe - UDP Send - 10.1.2.3(MyServerLocalIP):64881 -> 22.33.44.55(MyHomeInternetIp):44436

BTSync.exe - UDP Send - 10.1.2.3(MyServerLocalIP):64881 -> 22.33.44.55(MyHomeInternetIp):44445

BTSync.exe - UDP Send - 10.1.2.3(MyServerLocalIP):64881 -> 22.33.44.55(MyHomeInternetIp):44502

BTSync.exe - UDP Send - 10.1.2.3(MyServerLocalIP):64881 -> 22.33.44.55(MyHomeInternetIp):44574

BTSync.exe - UDP Send - 10.1.2.3(MyServerLocalIP):64881 -> 192.168.15.15(MyLaptopLocalIP):44253

any ideas?

additional:

-from my LabServer i can successfully telnet 192.168.15.15(MyLaptopLocalIP):44253

-using another Router at home it had worked flawlessly, i guess due to UPNP.

funny enough: my laptop is trying the correct InternetIp:Port 33.44.55.66(MyCompanyInternetIP):64881 but as i wrote i dont have portforwarding on the LabServer side.

Thanks in advance

Ragnar