A method and circuit for providing adaptive suppression of signal crosstalk appearing on a common return wire in a signal cable connected to a device. The method steps comprise connecting an adjustable negative resistance circuit between the common wire terminal and a common point at the device; determining an auxiliary current (Iaux) such that is flowing through at least one of the cable wires and returns through the common wire; sensing the voltage between selected at least one of the cable wire terminals at the device port and the common point, while ensuring that this level is substantially affected by Iaux; measuring a level of the sensed voltage according to a predefined level measurement procedure; and adjusting the negative resistance so as to nullify said voltage level, thereby effectively cancelling the common wire ohmic resistance.