WNDR 3700v5 disconnect after 5min in games

Hi, 

I own a Netgear WNDR 3700v5 since 3 weeks. Got the latest firmware on it V1.1.0.30_1.0.1

I have the problem that i get disconnected at World of Tanks and Call Of Duty 4 after exactly 5 minutes.

I use a cable connection and not WiFI.

At the time of the disconnect my internet is still working and i can use the internet or teamspeak. Only the connection to the game is lost. The Problem with Call Of Duty 4 i get fixed with opening the ports for the game. I also try the same thing for World Of Tanks but it still dont work correctly. The disconnect is happen one time after i start the game. If i reconnect again to the Wolrd of Tanks server i dont get disconnected again for the time i run the game. Next disconncet is happen if i restart the complet game. 

At the World of Tanks website i found the follow port informations:

IPs: 92.223.20.0-92.223.20.255

All destination UDP ports: 20013, 20014, 20018, 32801-32825

TCP game ports: 80, 443, 5222

UDP game ports: 53, 3432, 3478, 3479, 5060, 5062, 12000-29999, 30443, 32800-32900

Allow WorldOfTanks.exe to use UDP and TCP protocols.

If i look at my router log i see:

[LAN access from remote] from 74.201.98.241:3478 to 192.168.1.50:25793

So the port the game use is 25793? 

Would be nice if someone can help me :)