Only since you got the router? Hmm ... because CableVision is also known by other names such as Optimum Online. They are known to not be overkeen about p2p use. If you search the word Cablevision on the forum, you'll get the idea. Optimum online is listed here ISP's known to BLOCK or Filter p2p or specifically Limewire. But as far as I know, they don't block ports in all areas of their territory. Go to LW's menu bar, Tools>Options>Advanced>Firewalls & change the listening port to 64049 or 50012. This last one seems the best for cablevision.