Na documentação do apache:
Prior to 2.3.11, NameVirtualHost was required to instruct the server that a particular IP address and port combination was usable as a name-based virtual host. In 2.3.11 and later, any time an IP address and port combination is used in multiple virtual hosts, name-based virtual hosting is automatically enabled for that address.
This directive currently has no effect.
A solução para o seu problema é remover a diretiva NameVirtualHost.