This is a strange problem that I have found a few people having but no answers.
I recently started playing ARMA II: Combined Operations and DayZ. Everytime I play anything related to Arma the connections from my computer to the modem/router stops and starts at random times and for a random period of time. No other program or game makes my internet connection act like this. When I try to use Google Chrome or Firefox I get an error related to DNS and no other computer or device in my household does anything like what this computer is doing.
Router: WRT300N ( Linksys)
Modem: Qwest M1000
Here is what I have tried ( All of them have failed):
Disabling the firewall
Checking for viruses ( Clean )
Disabling anti virus
Plugging the Ethernet cable from my computer to my router into the modem.
I have this same problem. It does it with both the Play withSIX launcher and with Dayz Commander. Dayz Commander crashes too. The only way to get my internet back is to reboot my modem. I read somewhere that people think it's because there are too many connections being made and the modem can't handle it. The 'fix' was suppose to be limiting the default # of connections. That 'fix' didn't work for me.
I ended up doing the manual install of Dayz, which works well, but updating is more of a pain.