Kaltura_Client_Exception thrown

Invalid KS "YmY2M2YyNWQwM2ZkODViZmI0YWMyYmJlYWJiMTYwNGIwM2IzMmY4MHwxMDE7OzE0OTU2MjM5NDM7MjsxNDk1NTM3NTQzLjI5NDk7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"