Check you httpd error log, my error log had this in it,
PHP Fatal error: 'break' not in the 'loop' or 'switch' context in /usr/share/ocsinventory-reports/ocsreports/plugins/main_sections/ms_doubles/ms_doubles.php on line 61, referer: http://ocs/ocsreports/index.php?function=pluginsmanager
By putting // in from of the break; at line 61 cleared up my issue with blank page on duplicates.