I've recently factory reset my UC520W and I set up the SIP Trunk and the Incoming Dialing DID numbers. I can make outbound calls just fine. But I can't get incoming calls. When I call the DID it just ends the call. here is a debug of the debug ccsip messages
Right you are Paolo. After re-looking at the messages I realized later that day it was some NAT issue. I passed through the DHCP public address from my home DSL modem to the UC system and added an ACL to permit incoming calls. Everything is working as expected. Having little to no sleep makes you overlook the simple stuff zzzZZZzzz...
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