ahassouna

Hi all, I really need help with a problem in my ip cams. I got 2 dahua IPC-KW12W and an NVR Dahua DHI-NVR4104 both cameras have been set correctly on router with wifi and NVR via Ethernet. I gave each cam a static ip and accordingly reserved that ip on the router for each aswell as the NVR. the cameras work for a small amount of time then one of them keeps rebooting and disconnecting every 10 -30 seconds then it becomes stable then the other one does the same (problem switches between the 2 cams). I updated the NVR firmware and same problem, I logged on DMZ on router and gave it the NVR ip and still same problem, I opened the 37777 and 37778 ports on the router on udp and tcp and same problem. what is wrong here and I need advise please, much appreciated. Device TypeIPC-KW12W Software Version2.420.0000.0.R, build : 2014-09-24 WEB Version3.2.4.213946 ONVIF Version2.4.1 TypeDHI-NVR4104 Record Channel:4 Web:3.1.0.5 System Version:3.200.0000.6.R Build Date:2014-11-27 (updated to latest one which is 9.R)