Hi all, i have a CS1K (7.6) SIP trunked to an IP Office (8.1) and for whatever reason it will not pass a call from the CS1K to IPO, but from the IPO it can call the CS1K. All my DSC's, NRS endpoints, routes, trunks, etc have all been configured and bench tested. The system sat next to the CS1K and with a local TLAN IP assigned to the IPO WAN port as well as the NRS endpoint, it passed calls in both directions with the CS1K. Once installed at the remote site and of course reconfigured with the correct IP address all around, the weird part is that with everything configured as UDP (NRS endpoint, Layer 4 transport), the IPO can call the CS1K, but not the other direction. When i set everything up with TCP, the CS1K can call the IPO, but not the other way. There is no firewalls in use on the IPO and on any of my distribution switches from what im being told. I have installed many of these systems in the past using the same basic configs and they all work. The fact that it works on the bench with no problem tells me there is an obvious routing issue, but im not a network guy, so i am at a loss. Any help would be appreciated. Thanks