One thing to do, if your going to have SB and ABE enabled, I recommend disconnecting ALL other wired and wireless devices from the router, save one wired LAN PC, during the test time. It shouldn't take 24hours to complete it's speed testing. Other devices could be interfering with the test. So try testing with with out any other devices connected. Once it completes the test, then connect everything back up.
If you use SB and your streaming with CC and gaming with the PS4 at the same time, try lowering the priority for CC and see if this helps. Make sure that that priority for the PS4 is 1.
You have a good ISP modem, I have this one as well. I like the Motorola SB 6 series modems.
D-Link is aware of some issues with Sony products.
Keep us posted...