Turns out my modems firewall was blocking access. I rebooted my modem and now it works.
Still don't know why a device with one static IP could connect on several other IP's.
maybe there were already some exceptions for the IP address the cams were on in the firewall, like that IP was used in the past for connecting some other device to the internet or your local network? I notice sometime I get funny happenings on my network because I have a 4 port switch (I use for my mining hardware and wallet server) which is completely autonomous setup wired to the router and uses 192.168.1.x for its IPs but so does my main router out of my laziness. Sometimes some of the wireless devices as they connect to the main router will get one of those IPs already assigned to stuff connected to the 4 port switch or vice versa. This happens If conditions are "right", which i haven't figured out how to reproduce..I'm thinking I have to be rebooting the switch while something else connects wirelessly, IDK..
I haven't setup the router for MAC address filtering yet though. Which would probably take care of the problem but could prove to be a PITA if I forget I did that. Have you tried that yet?
no I haven't messed with mac address filtering. I have a block of 16 IP addresses, so it's pretty much 'plug and play'. set the device to a static IP, make sure the net mask is correct and boom. your done.
I'm blaming the dvr system.
I had a NAS do that once at work. Was fine for two years, then one day it showed up on 3 other IPs - you go to a sever, and instead of the server login, you get the NAS login. strange.
I suppose some record files in the router/modem could have go corrupt ie., port forwarding, or something.
All well, it's working now.