Hi all, After a bit of learning and blowing away my setup a few times to wring out some early problems I've got the following setup (apologies for the crude diagram, everything is on my local network): PSTN | | SPA3102 --- WRT54GS (connected to Internet) --- 3CX Server --- 2 softphones | | Telephone My problem is that when I call out from the telephone (connected to the SPA3102 which is programmed as an extension of the 3CX server) I can hear the call recipient but they cannot hear me. If I force my call to go out over the PSTN on the SPA3102 the call recipient can hear me. The softphone clients have no problems with either making or receiving VoIP and PSTN calls. Furthermore, when an inbound call comes in from either VoIP or the PSTN to the regular telephone the remote party can hear me without a problem. When I call another extension from the telephone to either softphone it also works fine (and also vice versa). The problem only manifests itself when I use the regular telephone to place a VoIP call. The call setup and termination work as expected. Things I have done are: 1) Punched holes in the firewall on the 3CX server, 2) Completely disabled the firewall on the 3CX server, 3) Added STUN server details into the SPA3102, 4) Setup SPA3102 as a PSTN gateway on the 3CX server (which works), 5) Setup Line 1 on SPA3102 as an extension on the 3CX server (also works), One thing to note is that I have connected the WAN port on my SPA3102 to my WRT54GS. I don't want to use the router functionality on the SPA3102 as the WRT54GS already performs this task. I did have the SPA3102 connected via the LAN port originally but read somewhere that I should have it connected via the WAN port to my existing router. Any ideas folks? My wife isn't too worried as long as she can receive calls via her softphone (which works like a charm) but I'd like to have it all working as it should. Thanks in advance!