DVD Duplicator

We have been having several problems with our DVD Duplicator. Firstly the top source drive no longer works. I have spoken to you recently and was told to open it and try pushing in the cables. This did not work. I have also tried re installing the driver but this did not work either. Also most of the drives keep failing and only one or two will work. As the source drive does not work the source keeps changing between the writable drives. I have tried using different disks but this also didn't work. I would really appreciate it if you could sort out this problem as the duplicator is very important to use, as it is used to mass produce our showreels. Thanks, Will