Clonable post type field count not zero with nothing selected

Hi,

I’m using post type metabox with ‘clone’ and ‘sort’ option.
I haven’t selected any posts, but rgm_meta has zeros in the array.

Get filed Value:

$posts_related = rwmb_meta( 'post_related', array(), $id );
var_dump($posts_related);
array(1) {
  [0]=>
  int(0)
}

I want the array to be empty if nothing is selected.

Field settings:

array (
    'id' => 'post_related',
    'type' => 'post',
    'name' => 'title',
    'post_type' => array(
        0 => 'post-type-1',
        1 => 'post-type-2',
        2 => 'post-type-3',
    ),
    'field_type' => 'select_advanced',
    'clone' => 1,
    'sort_clone' => 1,
),

*I can select multiple in Select Advanced, but I can’t change the order, so I use a ‘clone’.

Regards,