Kaltura_Client_Exception thrown

Invalid KS "MzhlMTc0NThiZjEzNjRjN2RlOGQxNDk4ZTE5NTc3ZDFhMjM4ZTdiMXwxMDE7OzE0NzQ5NDgyMTM7MjsxNDc0ODYxODEzLjU1NDg7QW5vbnltb3VzO2VkaXQ6Kg==", Error "-1,INVALID_STR"