Item (Mage_Review_Model_Review_Summary) with the same id "0" already exist

#0 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(32997): Varien_Data_Collection->addItem(Object(Mage_Review_Model_Review_Summary))
#1 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/Mage_Review_Model_Review.php(171): Varien_Data_Collection_Db->load()
#2 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/Mage_Review_Model_Observer.php(79): Mage_Review_Model_Review->appendSummary(Object(Mage_Catalog_Model_Resource_Product_Collection))
#3 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(22191): Mage_Review_Model_Observer->catalogBlockProductCollectionBeforeToHtml(Object(Varien_Event_Observer))
#4 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(22164): Mage_Core_Model_App->_callObserverMethod(Object(Mage_Review_Model_Observer), 'catalogBlockPro...', Object(Varien_Event_Observer))
#5 /var/www/vhosts/hgtbearing.com/httpdocs/app/Mage.php(448): Mage_Core_Model_App->dispatchEvent('catalog_block_p...', Array)
#6 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/Mage_Catalog_Block_Product_List.php(164): Mage::dispatchEvent('catalog_block_p...', Array)
#7 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(2881): Mage_Catalog_Block_Product_List->_beforeToHtml()
#8 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(2600): Mage_Core_Block_Abstract->toHtml()
#9 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(2544): Mage_Core_Block_Abstract->_getChildHtml('product_list', true)
#10 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/Mage_Catalog_Block_Category_View.php(90): Mage_Core_Block_Abstract->getChildHtml('product_list')
#11 /var/www/vhosts/hgtbearing.com/httpdocs/app/design/frontend/base/default/template/catalog/category/view.phtml(70): Mage_Catalog_Block_Category_View->getProductListHtml()
#12 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(3677): include('/var/www/vhosts...')
#13 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(3708): Mage_Core_Block_Template->fetchView('frontend/base/d...')
#14 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(3722): Mage_Core_Block_Template->renderView()
#15 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(2882): Mage_Core_Block_Template->_toHtml()
#16 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(13832): Mage_Core_Block_Abstract->toHtml()
#17 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(2882): Mage_Core_Block_Text_List->_toHtml()
#18 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(2600): Mage_Core_Block_Abstract->toHtml()
#19 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(2544): Mage_Core_Block_Abstract->_getChildHtml('content', true)
#20 /var/www/vhosts/hgtbearing.com/httpdocs/app/design/frontend/default/MAG090198/template/page/2columns-left.phtml(71): Mage_Core_Block_Abstract->getChildHtml('content')
#21 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(3677): include('/var/www/vhosts...')
#22 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(3708): Mage_Core_Block_Template->fetchView('frontend/defaul...')
#23 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(3722): Mage_Core_Block_Template->renderView()
#24 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(2882): Mage_Core_Block_Template->_toHtml()
#25 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(29425): Mage_Core_Block_Abstract->toHtml()
#26 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(14225): Mage_Core_Model_Layout->getOutput()
#27 /var/www/vhosts/hgtbearing.com/httpdocs/app/code/core/Mage/Catalog/controllers/CategoryController.php(161): Mage_Core_Controller_Varien_Action->renderLayout()
#28 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(14253): Mage_Catalog_CategoryController->viewAction()
#29 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(18637): Mage_Core_Controller_Varien_Action->dispatch('view')
#30 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(18171): Mage_Core_Controller_Varien_Router_Standard->match(Object(Mage_Core_Controller_Request_Http))
#31 /var/www/vhosts/hgtbearing.com/httpdocs/includes/src/__default.php(21207): Mage_Core_Controller_Varien_Front->dispatch()
#32 /var/www/vhosts/hgtbearing.com/httpdocs/app/Mage.php(684): Mage_Core_Model_App->run(Array)
#33 /var/www/vhosts/hgtbearing.com/httpdocs/index.php(88): Mage::run('', 'store')
#34 {main}