It's a multi-level issue that is not entirely on SE's end, not entirely within their power nor responsibility to resolve--so you need to bring the ISP's in to help out (yours, theirs, and all the others in between).

Open a support ticket with both your ISP and SE, giving specifics about your connection---preferably including the results of a tracert to the 199.xxx.xxx.xxx IP your client is using. At the very least, include the IP address of the server your game actually is using and let SE know who your ISP is and what city/state. This gives them a glimpse of where you are coming from and going to, and affords a means to at least have a list of all the players in between you and SE. With any luck, it may provide some clues as to a potential choking point in route they can investigate and hopefully get at least that part of your problem resolved.