Well, I got some information regarding the 657. New FW is to be released soon, no mention of what it fixes however I presume it in regards to WiFi and probably Samsung and or Motorola client device operation with the 657. Bad news is is that they are not going to do anything about IPv6 operation since the 657 is headed for EOL from what they say.
Sorry to be the bearer of bad news. I personally feel that the 657 didn't get enough TLC during it's life span.
It was said that if IPv6 users need help with the 657, to call in to D-Link support and get a solution, weather that be a FW fix or maybe something else, I don't know. So please contact D-Link support directly on the phone. Ask for level 2 or 3 or higher support I would recommend. It has been a good router, for me at least. I presume the WiFi issues seen are isolated to some specific client products and I'm hoping that D-Link will address them before they officially stop development.
Please be patient while we wait on the next FW build. I'm keeping an eye on it's arrival. The new FW should include the Samsung issue seen and was mentioned that this effects this model router, the 655 and 825 series. The 655 Rev A has now been fixed and FW was released. I presume Rev B could see a release as well. I haven't seen anything for the 825 yet.
I'll keep everyone posted.