Odd. I find Firefox handles .gifs better than Chrome for me.
I found the problem. It is the Kaspersky Add-on for Webbrowser. Just disabled it and it's really smooth now. Didn't even know that Kaspersky is blocking gifs...
Anyways, thanks for trying to help me. I appreciate it.
Edit:
Spartan Ops netcode details?
Hopefully they tested the netcode with different connections and with people from other countries. I hope they will not follow Bungie's mistakes there.