avg response time for AMF request in SoapUI

Hi,

I have a problem comparing the avg response time for an amf request in SoapUI and in an amf plugin for Firefox : they are not the same at all.
For example, for a "connectUser" amf request :
- SoapUI displays an avg response time of 4761msec
- the amf plugin for Firefox displays an avg response time of 125msec

Could you please explain this difference that is a big problem for us as we execute performance tests on a SoapUI scenario. Is there some configuration to do in SoapUI for amf requests ?

Thank you for your answer.

Best regards.