Virtual Service invocation latency

Hi, I have a webservice which I virtualized using CentraSite Active SOA. I then successfully deployed the virtual service to the Mediator target. The problem is that when I call the service directly, it take e.g. 3 to 5 seconds but when I call the virtualized service, it takes 30 to 120 seconds. Please help me resolve this issue as I’m clueless what the problem is.