A method for modification of a cepstro-temporally smoothed gain function of a gain function resulting in a bias compensated spectral gain function is provided. The cepstro-temporal smoothing increases the quality of an enhanced output signal, as it affects only spectral outliers caused by estimation errors, while the speech characteristics are well preserved. However, due to the cepstral transform, the temporal smoothing is done in the logarithmic domain rather than the linear domain, and hence results in a certain bias. Thus, the method for a general bias compensation for a cepstro-temporal smoothing of spectral filter gain functions that is only dependent on the lower limit of the spectral filter-gain function.