def METHOD_NAME(self):
    """Check that scrunching 2 spans changes header correctly"""
    self.shape_settings = [-1, 1, 2 * 2]
    self.gulp_nframe = 101
    with bfp.Pipeline() as pipeline:
        data = blocks.sigproc.read_sigproc([self.fil_file], self.gulp_nframe)
        call_data = CallbackBlock(
                data, self.check_sequence_before, self.check_data_before)
        scrunched = blocks.scrunch(data, 2)
        call_data = CallbackBlock(
                scrunched, self.check_sequence_after, self.check_data_after)
        pipeline.run()