Insane Delay problems

For the last 3 or so days i'm experiencing 5 seconds of delay every few seconds , having the same ms as usual so no real lag... my internet connection is working fine , i don't have problems with any other game/stuff except this one.
Now i just had to close the client because i had a 1 MINUTE DELAY which is ....wtf? I deleted cache , logged back in and now it is fine...
Any ideas what could be causing this or how to fix it?

Flush your DNS, turn off firewalls, and make sure no one else is on your network. I'm assuming that other players aren't experiencing a similar issue.