do not set SSNR to zero for same channels, use inf instead

        ssnr = np.round(10 * np.log10(10 ** (np.sum(ss, axis=0) / segment_counter) - 1), 2)

    ssnr[segment_counter == 0] = -np.inf

    # set to zero for channels with no diff (this handles e.g. the corner-case of an all-zero channel in both ref and dut)

    zero_diff_mask = np.asarray([np.all(diff_sig_norm[:, c] == 0) for c in range(ref_sig.shape[1])])

    ssnr[zero_diff_mask] = 0

    return ssnr