To make a valid comparison you need two A-8 units one on the current firmware and one on the former, comparisons must be unsighted.
It is imho extremely unlikely a change of firmware will affect sound quality, I haven’t noticed any differences with my A-8 here.
Keith
Agreed with your comments.
Yet..., I listened to my A8 with FW 1.2.60 for little over 6 weeks, and my ears got pretty used to the sound character, which I really liked. This sound is the reason for me to go with A8 and I gave up my A6ME, for it. My idea was to use it as an all in one Streamer, DAC and Preamp solution and to be powered with a power amp. As soon as I updated to 1.2.74 Beta, I felt the difference. Maybe this difference is not measurable as you have suggested.
The wide sound stage became more narrower, the instruments I heard in different areas of that sound stage became more concentrated towards the middle and became mixed up with the vocals. (tested many times by playing my favourite tracks over and over again. The beautiful midrange, had earlier, lacked the luster and the sound leaned towards the bright side. (The sound was almost 3D earlier as if you would listen to a live artist playing right in front of you, but not anymore)
This is what I experienced after the update to 1.2.74 and then 1.2.80. Thank you.