WARNING: unable to obtain file audio codec with ffprobe

Raise code

            raise AudioConversionError(err.msg)

    def run(self, information):
        path = information['filepath']

        filecodec = self.get_audio_codec(path)
        if filecodec is None:
            raise PostProcessingError('WARNING: unable to obtain file audio codec with ffprobe')

        more_opts = []
        if self._preferredcodec == 'best' or self._preferredcodec == filecodec or (self._preferredcodec == 'm4a' and filecodec == 'aac'):
            if filecodec == 'aac' and self._preferredcodec in ['m4a', 'best']:
                # Lossless, but in another container
                acodec = 'copy'
                extension = 'm4a'