For the past month or so, I have been unable to stay connected to a black ops game.?

I used to be disconnected from Xbox live completely and every device on my network would be disconnected from the internet every 5 minutes (due to our ISP tower getting struck by lightning) but now its just games. I can sometimes stay in for a whole game but usually I'll be disconnected within 5 minutes. My NAT is open, UPNP is enabled, ISP is Partnership Broadband. Also, the disconnection is even more frequent if other network devices are connected to the internet.