A stream monitor can request a streaming media server to send stream records associated with streams currently being served. The stream monitor uses the stream records to test streams being served by the streaming media server. The stream monitor can concurrently test multiple streams for connection errors, silence errors, metadata errors, and other errors. The stream monitor initiates a data stream monitoring application, initiates a heartbeat timer to produce a periodic heartbeat signal and delivers, to a host webpage, a last data stream record to be tested in conjunction with the heartbeat signal. When a periodic heartbeat signal is not received in a timely manner the monitor restarts the stream testing application at the last data record tested.