The Voice Recording System provides a comprehensive solution for trunk-side and extension-side recording. It can accommodate Primary Rate and Basic Rate ISDN, analogue trunks and extensions, two-way radios, VOIP recording, and digital extensions on various PABX systems. Any combination and quantity of these audio circuits can be accommodated simultaneously within a server or a server cluster. The software makes use of a standard PC architecture in combination with custom hardware interface modules. These modules utilise USB connectivity to the server (Universal Serial Bus), providing a number of advantages over the traditional PCI technology usually found in similar professional systems. These advantages include a 'hot-swap' capability which allows maintenance, expansion and reconfiguration to be performed without switching off or restarting the system. The system employs a number of proprietary Black Boxes to interface to the various types of telecommunication lines used in the telephone network. The interfaces use non intrusive connections (high impedance) to capture audio and data from these lines.