My experience with the Codex was there is an audible difference between the balanced and unbalanced connection in my system. I was using Audience AU24 SE rca cables from the Codex to my VAC preamp initially and then changed to the older model Audience AU24e balanced interconnects. There was an improvment in soundstage and space around instruments noted in my system. Ayre was designed to perform best using balanced connections according to many reviews I have read. My VAC Renaissance V preamp is connected with balanced cables to an Ayre VX-5/20.
Rick
Rick