Random LONG lag spikes

[alaiwy0503]

I am having a weird issue with one of my computers where I get into really long random lag spikes. It will keep me stuck in casting new spell or queue'ing up actions for 10-45 seconds at a time. I don't have any dual core issues or anything. I am on a stable internet connection but am using a wifi extender. I have no packet loss in other applications or games.

Has anybody else experienced this or have anything to try? it's almost unbearable