After contacting the president of Comcast, he sent a bunch of techs to find the problem. Turns out it was interference from a home down the street. Apparently it could not be detected by normal means. The 4th tech that came out to my house actually knew a thing or 2, and when he checked the ping test results he knew something was wrong. Internet has been fantastic ever since. I appreciate all of your input!
I've been investigating lag spikes for weeks now on my internet, and I can't seem to fix this error (DNS server not responding). I can connect to the internet just fine, but lag spikes really kill my gaming experience. I've gone through multiple gateways, comcast laid a new line and replaced an old splitter, but still they can't fix it. They say my signal is just fine and want me to upgrade my speed. This happens on multiple devices (computers, Xbox, etc.). When I changed to a public DNS, the error goes away, but the lag is still there. My connection is fine for minutes at a time, but gets spikes that eventually DC some of my games and Xbox Live, which is rather annoying. It doesn't seem to happen at any specific time of day either. This happens around the clock. Does anyone have any ideas? I'm thinking about trying to change my ISP, but Comcast has a monopoly around here.

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