I had a NEC sales rep refer me to someone that was having trouble with a ds2000. I go out and the previous tech had took cat5 patch cords stranded wire punched on a 66 block. They had bad static not to mention the split pairs cause they were 568b not rj61x cords. Half the phones sat their saying "System startup" on the display. Replaced the cords and bingo! I hope that fellow didn't refer to hiself as a "telephone tech".