Moving slowly in some zones

[rubiks]

I first noticed it in Greater Faydark. I was moving more slowly than another player even though we both had jboots and neither of us was encumbered. The other player said i was moving forward then snapping back while running. All other zones worked fine. It happened again In everfrost a couple of days later, and now it is happeneing in EC. Someone described what it looks like as "rubberbanding"

I had dual core issues, but i used Duxa's installer and fixed them. But sometimes when I am online for an extended period of time, I will start having the dual core issues again and will have to restart my computer.

Any ideas? I need to fix this before it affects my ability to play the game