IP cam PTZ off/on

[rustoleum]

I added 7 IP cameras (5) fixed and (2) PTZ's to my NAS 720+ system (with the current updated version) by hardwiring them to my Ubiquiti POE+. All the cameras work properly except for one PTZ) which is a Amcrest PTZ (ONVIF complient) and it continues to disconnect off and on. I even replaced it with the same PTZ camera after thinking the original camera was bad. Then I decided to purchase another PTZ from a different manufacturer to replace the Amcrest, now I am still getting that PTZ camera to disconnect like the Amcrest. I have to manually go into the Surveilance Station on NAS each time to reset the PTZ camera. This happens on a daily basis and other times the PTZ will go off and online many times during the day and night. My network is very robust and can handle many cameras to be added but with only 7 cameras. In fact, one of the 7 cameras is a operating HIKVISION compatible PTZ cam that's been working great and has not disconnected off/on. However those 2 Amcrest PTZ cams and the other PTZ mfg. still constantly disconnect. The PTZ's work great for awhile, then everyday the PTZ disconnects and restarts, goes off and on for hours like that. I even placed the PTZ in a closet and hooked directly to my POE+ using a short cable to the POE and to avoid any frequency's or other signals that may interfere with it but yet it still does it. Anyone have a similar problem using the Surveillance station with PTZ IP cams?