Virtual Host Root and Virtual Host Document Root (under Virtual Host => General) are two different things.
Virtual Host Document Root usually should be $VH_ROOT/public_html. In your case, $VH_ROOT should be "/home/s4music/"; config file should be $VH_ROOT/ms.xml which needs to be readable by admin webserver user 'lsadm'.
For vhost level throttling, set at a lower number such as '4K' to start and see any difference.
BTW, regarding "Running short of concurrent connections", you can try increase Max Connections (Admin Console => Server => Tuning), say from 2000 to 5000, and see any difference.
Last edited by webizen; 06-14-2013 at 01:21 PM..