The Cisco SPA122 has TWO teleco ports and ONE MAC address. When I try to create two extensions within 3CX, I can use the MAC address of the SPA122 only ONCE. Do I care? The two extensions are registered and seem to work okay. I want to use the SPA122 to hook up to standard analog phones and create two extensions. The SPA is defined in our router by MAC address and IP address. Any comments? I am not clear on why I can not use the MAC address for each definition of the extensions.