Spikes in connection (possibly due to router?)

Whenever I play online games like DoD:S or RvS etc. I get lag. I'm on a Comcast cable connection and this shouldn't happen. So I went over to DSL reports.com and did a line quality test. Look what I got:

http://www.dslreports.com/quality/nil/1936381

I guess all the "lag" was coming from these spikes in my connection. I don't know why my connection is spiking like this, but it makes games unplayable online.

Could anyone tell me why I might be recieving this problem and more importantly how I might go about fixing it?

Thanks.

Are you idling in IRC while you're playing?

from what I can see on those tests the problem is with 2 hops.

Hop Host LOSS Rcv Sent Best Avg Worst
1 jfk-core-01.inet.qwest.net 0% 60 60 0.79 2.08 74.77
6 tbr2-cl3.dvmco.ip.att.net 0% 60 60 66.44 69.29 218.87

those 2 hops are the only ones where the low and high pings vary greatly... everything else looks consistent.

Shouldn't those graphs be pretty much a plateau, though? It's not good to have a quick response then a slow response shortly after or even building up to that regularly?

...and no, I'm not idling in IRC.

Anyone?