I just got my ZD3 today. It also shows NONE for the bitrate on HDMI. Mine came with firmware 1.06.
I use HDMI ARC as my main audio input. Great feature, and the main reason I bought this DAC. I run a 2ch amp for movies and TV and don't want a full AV receiver. Overall I'm very pleased with it, sounds great and has almost all the functions I wanted in a DAC.