An alarm system includes an alarm panel that signals sensed alarm conditions at a premises to a monitoring server over a packet switched data network. The alarm panel also senses and buffers audio at the premises. In response to a sensed alarm condition, buffered audio, buffered prior to signalling the sensed alarm condition, is transferred to the monitoring station. The alarm panel may further receive live audio from the premises. Data representing live audio and buffered audio may be transferred concurrently, allowing an operator at a monitoring center to listen to audio arising from events before and after an alarm is signalled. The alarm system may further allow real-time communication between the monitoring center and panel.