Hi, I've got the same flood here on port 445, across my LAN. If I block that port, I get a flood instead via port 139.
There was 1MB/s upload/download between my Windows 10 machine and a Raspberry Pi 3 (Raspbian 4.9.24-v7+). I blocked that and had the same flood between two Raspberry Pi 3s. The same thing happened if I fired up my Lubuntu boxes. I can't remember if it was the 4.4.0-75-generic or the 4.8.0-29-generic, and I can't re-enable Samba right now on the network, as it's "live" and I don't want to disrupt the web service. Not sure if I can attach a Wireshark screenshot of traffic between the two Raspberry Pi 3s (?) Regards, Eric Twose.