I'm in the process of configuring and testing 3CX for the first time. I've managed to segment the data and phone networks using two network cards (NOT Vlan'd) I have the 3CX App on my iPhone, and 3CX client installed on my Desktop PC, and both of them connect to 3CX over the Data network (192.168.16.xxx). Both were seen in "phones" before being provisioned (not sure if that's important but will explain later) I've added the 2nd NIC and connected two hard phones (Yealink T21P E2 and a T27G), both of which have IP's in the 172.16.12.xxx range. the phones initially weren't seen under "Phones" in 3CX, I had to manually provision them to each of their respective extensions before they appeared. Using the iPhone and Windows apps, I can call the two Yealink phones that are on the 172.16.12.xxx range. However, the two Yealink phones can't outbound to eachother, or the iPhone app / windows client sat on the 192.168.16.xxx range. the calls don't appear in the call log in 3CX, and the message that displays on the Yealink phones are simply "Call Failed! (ext) Decline" if anyone has had this before, or can offer any advice, that'd be much appreciated.