I'd find it hard to be a backplane when the stations and trunks pin right out of the front of the cards.By your first post I'd guess the problem is with the trunk card itself or the co pairs are crossed coming into the building if the amphenols and blocks are ok.As for 209 running on the last pair and first pair of 2 different cards are they on different cables or is the cable split to more than 1 card?