I dont think its on the EEproms as ive had a simalar problem and swapped both the chips from another unit and it still doesnt work, i think it may need to be done using the riser programmer port ?? I dont know but as you say there is CAL and PRG links on there.... would be nice to know how to do this, as i have 3 units that have this problem, i do have an eeprom reader as well and tried to copy ove to the chips which did copy but still didnt work, thats why i directly swapped the chips over with no luck...