public function getNextUnansweredToken()
    {
        $tokenSelect = $this->tracker->getTokenSelect();
        $tokenSelect
                ->andReceptionCodes()
                // ->andRespondents()
                // ->andRespondentOrganizations()
                // ->andConsents
                ->andRounds(array())
                ->andSurveys(array())
                ->forRespondent($this->getRespondentId())
                ->forGroupId($this->getSurvey()->getGroupId())
                ->onlySucces()
                ->onlyValid()
                ->forWhere('gsu_active = 1')
                ->forWhere('gro_active = 1 OR gro_active IS NULL')
                ->order(array('gto_valid_from', 'gto_round_order'));

        $this->_addRelation($tokenSelect);

        if ($tokenData = $tokenSelect->fetchRow()) {
            return $this->tracker->getToken($tokenData);
        }
    }