jQuery sortable list placeholder issue

I have a sortable list. I have managed to sort into multilevel. But when an element from first level depth is inserted into second level depth the placeholder keeps running violently.

$('.sortable').sortable({ 
    connectWith:    '.sortable',
    cursor:         'move',
    placeholder:    'sortable-placeholder',
    handle:         '.block-title',
    cursorAt:       { left: 150, top: 17 },
    /*tolerance:      'pointer',*/
    scroll:         false,
    zIndex:         9999,
});
$('.sortable').disableSelection();

Here is my fiddle

from jQuery sortable list placeholder issue