Du måste frigöra din anslutning med metoden PDOStatement::closeCursor()
http://www.php.net/manual/en/pdostatement.closecursor .php
Jag tror
foreach($phones as $phone)
{
$stmt = db::getInstance()->prepare("CALL phones(:phone)");
$stmt->bindParam(':phone', $phone, PDO::PARAM_INT, 10);
$stmt->execute();
$stmt->closeCursor()
$result[] = db::getInstance()->query("SELECT @phone;")->fetchAll(PDO::FETCH_ASSOC);
}
borde göra det åt dig