Warning: Illegal string offset 'value' in _multiselect_build_widget_code()

I am getting this error.
Warning: Illegal string offset 'value' in _multiselect_build_widget_code()
in the following line.

elseif (is_array($value['value']) && array_key_exists('uid', $value['value'])) { // Field collections have them nested. User ref
$selected_options[$value['value']['uid']] = $value['value']['uid'];
}