Here's more results, from Line-Out, USB, S/PDIF: http://rmaa.elektrokrishna.com/Comparisons/Hifiman%20Line-Out%2C%20USB%2C%20SPDIF.htm
Same thing, it's just not a very good amp/DAC. I also tried the amp board from the second Hifiman, same results. Verified twice.
Sonic748i, I'm sorry, I know how proud you are of your Hifiman>RSA>JH13 rig. But yeah, maybe spend the $30 on a Clip+ and give it a listen. You might find that you really don't need to carry that brick around with you, and you get an actually working firmware (with gapless playback) as well.