Query meta field using between

Question

I'm trying to Query some lattitude and logitude and then I get some long numbers and apperently the Query dont like that.

Let says I have these in the database

Meta-key: lat 
Meta-value: 54.3415000 
Meta-key: lng
Meta-value: 10.1254100

and do a query like this:

$args['meta_query'] = 
        array(
            'relation' => 'AND', 
            array(
                'key'       => 'lat',
                'value'     =>  array( '53.82659686199116', '54.946076335668714' ),
                'type'      => 'NUMERIC',
                'compare'   => 'BETWEEN',
            ),
            array(
                'key'       => 'lng',
                'value'     =>  array( '8.429260683593725', '11.889954042968725' ),
                'type'      => 'NUMERIC',
                'compare'   => 'BETWEEN',
            )
        );

Then it works, BUT, when it looks like this:

$args['meta_query'] = 
        array(
            'relation' => 'AND', 
            array(
                'key'       => 'lat',
                'value'     =>  array( '54.10933293482647', '54.66906633195788' ),
                'type'      => 'NUMERIC',
                'compare'   => 'BETWEEN',
            ),
            array(
                'key'       => 'lng',
                'value'     =>  array( '9.294434023437475', '11.024780703124975' ),
                'type'      => 'NUMERIC',
                'compare'   => 'BETWEEN',
            )
        );

Then it does not work, even it is still between the 2 numbers.

Anyone have a clue what is going on here ? Must be some MYSQL stuff.

EDIT:

Here is what a mysql request looks like:

SELECT SQL_CALC_FOUND_ROWS wp_posts.ID FROM wp_posts INNER JOIN wp_postmeta ON
(wp_posts.ID = wp_postmeta.post_id)INNER JOIN wp_postmeta AS mt1 ON 
(wp_posts.ID = mt1.post_id) WHERE 1=1 AND wp_posts.post_type = 'branchenbuch' 
AND (wp_posts.post_status = 'publish' OR wp_posts.post_status = 'future' 
OR wp_posts.post_status = 'draft' OR wp_posts.post_status = 'pending' 
OR wp_posts.post_status = 'private') AND ( (wp_postmeta.meta_key = 'lat' 
AND CAST(wp_postmeta.meta_value AS SIGNED) BETWEEN '54.1833340338' 
AND '54.4636527622')AND (mt1.meta_key = 'lng' AND CAST(mt1.meta_value AS SIGNED) 
BETWEEN '9.76272625977' AND '10.6278995996') ) GROUP BY wp_posts.ID 
ORDER BY wp_posts.post_date DESC LIMIT 0, 10