Aastra 480i Phone Setup I've configured 3CX Phone System Version3.1.2434.0 and opened the correct ports on my router. The system works great when all the phones are behind the router with the 3cx system (calling between extensions, or to an outside line via our Vonage connection). When I connect from a remote location via a soft phone (X-lite), or via my ATA (Linksys SPA1001) everything works correctly (I can call extensions located behind the firewall in the office where 3cx is setup, or outside lines). However, while the Aastra 480i Phone (I followed the setup instructions offered by 3cx) works great when at the office behind the firewall with the 3cx server, it will not work from any remote location. The phone registers correctly to 3cx, but when I dial out with it (outside line, or other extension) they can hear me, but I can not hear them. While I believe most issues like this are caused by incorrect port forwarding, my ATA works well, and so does the soft phone from the remote location. The only think I can figure is that the Aastra phone has no option to configure a STUN server - and this is the only difference in how it is configured from the other working devices. Is there a way to 'work around' this problem without STUN support on the Aastra phone? I've included the logs below showing a call from the Aastra to an outside line: StratLink:nHangUp [CM104001] Call(22): Ext.102 hung up call; cause: BYE; from IP:xxx.xxx.xxx.xx CallLegImpl:nConnected [CM103001] Call(22): Created audio channel for Ln:10000@Vonage (xx.xx.xxx.xx:12992) with Media Server (xx.xx.xxx.xx:9078) StratInOut:nConnected [CM104005] Call(22): Setup completed for call from Ext.102 to Ln:10000@Vonage CallLegImpl:nConnected [CM103001] Call(22): Created audio channel for Ext.102 (192.168.1.5:3000) with Media Server (xx.xx.xxx.xx:9076) CallConf:nProvisional [CM103003] Call(22): Ln:10000@Vonage is ringing CallConf:nIncoming [CM103002] Call(22): Incoming call from 102 (Ext.102) to sip:email@example.com:5060 Any assistance is greatly appreciated! Thank-you.