I had the same issue with my linksys, and yes, it was a conflict with the ip's. Is my buddy pointed out to me was a that i has a nat type 3 eww. i needed a 2 and the way i got that was a DMZ. i put my ip address from my ps3 into the DMZ in the router. It worked like a carm, after that if i saw issues it was cause by my ips had changed on there own, so ended up getting a dlink, but thats how you do it, pretty easy fix.