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Hi, I have a problem with one PTZ camera (Bosch VEZ-513-EWCR) on my video surveillance system. It's analog camera connected with coax cable (video) and UTP cable (data) to fiber optics transmitter (model GE Security S732DVT-EST2). Video and data are transmitted between transmitter and receiver over two optical fibers. Fiber optic receiver (model GE Security S732DVR-RST2) located in security center is connected to the Dedicated Micros DS2 DVR (coax for video and UTP cable for data). The issue I'm dealing with is that after some time I lose zoom control on the camera and can't find the reason why this happens. The only way to get zoom control back is to restart the camera by pulling the power off. Camera has the address 10, connected to channel 10 on the DVR, uses Pelco-P protocol, Baud rate 9600, dip switch on optical transmitter and receiver are set on 4 (RS232). The thing that bothers me is the fact that everything works fine (PTZ controls, entering menu, patrol,...) when I power up the camera, and after some time zoom control just stops to work. Also, I have a few more PTZ cameras on the same DVR that are connected at the same way (Spectra II and III) which are working fine all the time. Also, I tried to connect the camera on my table with the same hardware (camera + FO transmitter + FO receiver + DVR) and had no problems with zoom in or out. Camera, FO transmitter and receiver are new, but the DVR and wires are old. If somebody has any idea what to do to resolve this issue, please advise.