A system and method are disclosed for recording and evaluating faults in event transmissions between security system components. A panel in a monitored building may send event signals to a receiver located in a central monitoring facility. Event signals may represent a status of individual alarms or sensors in the building, or they may provide a status of the system as a whole. If the quality of the transmission is substandard or in a format that is unacceptable to the receiver, the signal data associated with the event is recorded for analysis. Recording is controlled by a line card associated with the receiver, and the signal data is stored in local or remote memory. Signal data can be manually or automatically analyzed to determine the source of the fault. In addition, recorded signal data can be used to build customized software to recognize signals from previously unrecognized or faulty panels.