The method includes organizing a plurality of subscriber lines into a first group of subscriber lines and a second group of subscriber lines, the first group of subscriber lines at least including all the subscriber lines of the plurality of subscriber lines that do not support non-linear precoding operation and the second group of subscriber lines including the remaining subscriber lines of the plurality of subscriber lines; scaling first signals to be transmitted over respective ones of the first group of subscriber lines to confine respective intermediate transmit power levels at the input of a modulo unit and further to bypass or make ineffective the operation of the modulo unit; and processing the so scaled first signals and second signals to be transmitted over respective ones of the second group of subscriber lines through the first and second precoding stages.