My current setup and ill explain it as simple as I can

R710 server (I know there is some haters with this

8 IP POE Cameras (6 dahua 4mp and 2 dahua 5mp)
So the cameras are in most cases working well apart from one slight issue where the response on them are quite slow, I have tried various methods from what I can find mostly from google but its not helped much. Lowering FPS etc...
Now lowering the fps and a few basic changes like direct to disc and the cameras respond much better but not perfect the server is more than capable of handling this. I would like to add more cameras but until the slow response is resolved I do not wish to go any further. I am finding this both main BI and the UI3 without opera and without. Im hoping someone can enlighten me and help with this sticky situation.
All cameras are connected via a gigabit POE switch and hardwired straight into the server rack. 4 of the cameras run roughly a 100m cable on cat6 shielded aswell.