Communications jacks having flexible printed circuit boards with common mode crosstalk compensation

Communications jacks include a housing and a flexible printed circuit board that is at least partly within the housing. Eight input contacts that are mounted on the flexible printed circuit board, with the fourth and fifth input contacts forming a first differential pair, the first and second input contacts forming a second differential pair, the third and sixth input contacts forming a third differential pair, and the seventh and eighth input contacts forming a fourth differential pair. The plug contact regions of the input contacts are arranged in numerical order across a plug aperture of the jack. Eight output contacts are also provided, and the flexible printed circuit board includes conductive paths that electrically connect each input contact to a respective output contact. The fourth and fifth input contacts are mounted on the flexible printed circuit board at respective first and second mounting locations that are closer to a back end of the housing than are respective third and fourth mounting locations where the third and sixth input contacts are mounted on the flexible printed circuit board.