The system comprises a master module and slave modules able to be chain-connected and/or star-connected by means of a digital communication network, for example of the Ethernet type. The system is synchronized on the master module clock that supplies synchronization information to all the data frames it sends over the network. Each slave module reconstitutes the clock from the frames it receives. The data frames comprise data packets that can in particular be command data, audio data or video data. Each packet comprises a header describing the content of the packet. Each slave module knows at which location of a packet the data intended for it is located and at which location of a packet it can insert data.