A data recording system that includes a plurality of network interface cards that may be employed within a single recording device. Each card may be provided with a plurality of network connecting ports to receive packetized data, such as real-time protocol (RTP) streams. For each RTP packet stream being recorded, the system may note the sequence number for the most recently accepted packet and any packet received with a lower sequence number can be readily discarded. The system then may record payload associated with the RTP streams into an audio file saved on a storage device.