set your power supply feeding it to 90 volts to drop your current (less current less heat)and try to reduce the power supply load off of that power supply. SA or Cisco as they are now, made angled FWD & RTN jumpers to go from the interface board to the module. these have Ferrite beads on them to filter out high frequency noise also. are you using Prisma, DFB, or FP return?
This is CABL.com posting #347333. Tiny Link: cabl.co/mbCwj