The present invention is directed to a telephony communication interface device. The device includes a communication transceiver configured to communicate with a remote system via a predetermined communication channel. A control circuit is coupled to the communication transceiver. The control circuit is configured to determine a device operating mode status based on communication transceiver activity. The device operating mode status includes a telephonic communications mode and a remote system communications mode. An interface circuit is coupled to at least one telephone set. The interface circuit is configured to propagate voice telephony signals between the at least one telephone set and a telephony network in a telephonic communications mode and propagate voice intercom signals between the at least one telephone set and the communication transceiver in the remote system communications mode.