@fast,
probably not exactly addressing your questions. But, in comment's section there is a post by Christiaan Punter (hifi-advice.com) which might help you, with something on Aqua commented.
http://www.hifi-advice.com/blog/review/digital-reviews/spdif-dac-reviews/wadia-121-usb-dac/
probably not exactly addressing your questions. But, in comment's section there is a post by Christiaan Punter (hifi-advice.com) which might help you, with something on Aqua commented.
http://www.hifi-advice.com/blog/review/digital-reviews/spdif-dac-reviews/wadia-121-usb-dac/