could be something going on with your ISP or your network. make sure you powercycle your modem/router and disable anti-virus/firewall. also try performing a traceroute using this page and following the instructions. if you see any packet loss being anything other than 0% or 100% then theres a problem somewhere.
also ensure you're connected hardwire into your router rather than going with wifi. could also try deleting origin cache files to see if that helps.
