The reason I pointed to your network is because you seem to be the only one with this problem (possibly Alfred too). I don't have it, none of the people I play with that also use SEQ have this problem. So logically something with your particluar setup is the culprit...
The ping things were just a stab in the dark. You'd have to let them run for q few minutes atleast to have a chance at seeing something I bet. Granted EQ isn't a bandwidth hog, but it surely takes alot more than a simple ping, which would make ping less useful...