when it its in the failed condition, did you try entering the GET command and see what the response is? sound like you may have a cpu, or eeprom failing. would be interesting to see what the get responds with. maybe more then one parameter out of range, or the FCP saved setting is failing. type in FCP when it is operational, and record the floor counts, then enter it during the failure and see if they have changed. kind of strange it would do it intermittently. i would change the cpu, or change the eeprom. if you have a spare cpu, you can just swap out the eeprom onto the new card i believe, and do a new terminal backup, its been a couple years since i replaced a cpu, but i believe that is what i did, i know it was fairly simple. if you do swap the eeprom and it continues, probably bad eeproms. good luck