Urgent Help Please dahua camera system

[chrisrudkin 0]

Hi folks really hope somebody can help, i'm on a biggish site which i have installed a 35 camera system. im using a Dahua 64 channel nvr with 16 hardrive slots on the front. currently only has 6 slots in use. the ip cameras are running 2mp and 3mp in various warehouses. there are 2x 24 port gigabit poe switches, 1x 8 port 10/100 poe switch and 1x 24 port 10/100 24 port poe switch with 2 gigabit uplink ports. the issue im having is there are also 2x 32 channel nvrs. we are intergrating in with an IT company for that is already installed. if i plug 1 of the 32 channels in and load the cameras onto it the system works fine, but if i plug the 2nd one in to the system the cameras drop off the system and have periods of not recording. as soon as unplug one of them the system works fine again. i have gone through each camera and looked at the bandwidth used and most of the cameras are set up at: Stream 1 15 FPS, 2000KPS and Variable bit rate and stream 2 15FPS, 2000Kps and variable bit rate.