An audio network system that performs transport of audio signals between nodes by cascading a plurality of nodes each including two sets of transmission I/Fs and reception I/Fs, and circulating among the nodes in each fixed period an audio transport frame generated by a master node, the audio transport frame including a plurality of storage regions for audio signals, is configured such that when the configuration of the system is changed, loopback of the audio transport frame in each node and release thereof are automatically controlled to automatically loop back the transport of the audio transport frame at nodes at both ends and not loop back it at the other nodes to thereby form a loop transmission route among the nodes.