I have had problems with connecting my HX700 to a Dlink DIR-655 too. It would intermittently connect to the network, although the TV claimed that all (cable & connection) was well. I found what the problem was when I placed the router next to my TV and connected it with a short cable. It worked! Because the Dlink has a gigabit switch and the TV tries to handshake on that speed, it is important that you use a cable with gigabit specs. When I replaced the cable to upstairs with cat6 it worked fine. I could have solved it easier if either router or TV would allow fixing the speed on fastethernet, but unfortunately that isn't the case. I hope this will help you?
