1. A method for reducing noise signals and background signals in a speech-processing system, comprising: adaptively filtering an audio input signal s(t) to generate a prediction output signal sv(t) using a plurality of coefficients (c i (t); c 1 -c 4 ) to generate a plurality of prediction errors (sv 1 -sv 4 ) and generating an error (e) from the plurality of prediction errors (sv 1 -sv 4 ), where the prediction output signal sv(t) is the sum of the plurality of prediction errors; where the absolute values of the coefficients (c i (t); c 1 -c 4 ) are reduced by a plurality of reduction parameters (k).