Hello I have a third gen Apple TV. I have converted my CDs and HD Music to ALAC. Most of the content is 16 bit at 44.1K but the HD music is 24bit at 96k and 192K. I loaded all the music into itunes and it all plays fine. I have an HDMI compatible Home Theater preamp that I use to play the music. So I am using the HDMI audio on the Apple TV not the optical output. My questions are: Does the Apple TV and itunes truly support HD ALAC. If so, what setting do I have to adjust for the best sound quality? How is the HD music being processed? Is the HD ALAC music (24 bit at 96K and 192K) being directly passed through to my preamp or it being down sampled some where along the way. Thanks for your help.