Any Ideas why Opman 9.4 freezes up on Maps Tab

Any Ideas ?? Whenever clicking onto MAPS tab, the default view (all devices) never loads. the entire Opman instance becomes "frozen" (can't login from another session or use browser tabs) until application services are re-started. this install only has 153 devices so far, the server itself is not reporting any performance issues and is normal and responsive even when Opman is hung. Opman 9.4 is installed on 2008R2 12GB RAM 4-2.3 GHz CPU using the included postrgres DB (current size is 16 GB which seems high compared to MySQL based versions) I suspect it is a Postres issue but i do not have enough experience w that DB to speculate intelligently.Any Ideas would be helpful