As serial digital video signals become more prevalent in production facilities, the demand for multichannel audio increases. The 8920MUX provides a cost-effective solution for inserting or replacing one of the eight available groups of dual AES streams in a multiplexed serial digital video signal with embedded AES/EBU audio. The 8920MUX can multiplex up to two, dualchannel 20- or 24-bit AES/EBU audio streams (up to four discrete channels). The 20- or 24-bit AES streams are grouped together and given a unique group ID. This AES group is then inserted into the ancillary data space of the 525 or 625 serial digital component video signal. The 8920MUX is able to add a new AES group into empty ancillary data space, or it can replace an existing AES group—without disturbing the remaining AES groups. Digital audio inputs can be either 75Ω unbalanced or 110Ω balanced.