One a section of our modbus plus network we have a bridge plus and a 984 controller on one side of a fiber modem. On the other side of the fiber modem we have two more 984 controllers and five quantum controllers. When I try to add one more quantum controller the bridge plus and 984 controller on the other side of the modem start getting cable b framing errors. All devices use the MBKT type of connectors and we are well under the 1500 foot maximum cable length. Could anybody shed some light on this problem?