I am trying to use SIPP to load test Kamailio. I am using a combination with Freeswitch and Kamailio as an SBC with the calls being delivered to Asterisk. 

The problem seems to be with the ACK sent back from SIPP on response to the 200 OK. This ACK is not being forwarded by Kamailio and therefore FS drops the call.

I have scoured every page and tried everything so any help would be appreciated.

Thanks,

Keith