If, as it appears, the problem is related to faulty hardware, then any attempt to fix it with a software solution, is just not practical, because every time you change a Panel Memory or load a new set-up from SD Card or Floppy Disk, the fault will return. The only practical solution is to have a Technician investigate the hardware - i.e. the Modulation Potentiometer and its associated wiring, which I understand is the action Roger is taking.