Douglas, Thank you for a fine review. I had similar problems with position of connectors. My speaker cable wires are thick and don't bend 90deg. It forces them to go down on both sides of XLR input plug. Since wire on the outside of the plug encroaches on both 12V 1/8" connectors I had to force the 1/8" plug in (almost impossible).
I find performance of the bass phenomenal. There are low notes that were completely missing before (why?), not to mention better dynamics. That is really strange since my speakers are benign load (6ohm, 3.6ohm min) while Rowland 102 has 5Hz -3dB limit and DF=4000 at low frequencies. AHB2 has 0.1Hz -3dB limit and DF=350 at 20Hz. I also find improved overall clarity from bass to high treble. Unfortunately some recordings still sound veiled while some others now sound thin (veiled before). It sounds wonderful on fine records but also ruthlessly reveals shortcomings of the poor recordings. Imaging is improved, both width and depth.
I played drum solo on Chesky Records test CD and was absolutely stunned. It sounded like live set of drums playing in my living room. Bass control is better than before and the transients are fantastic. Pink Floyd's "Hey You" shook my windows and made me jump at the moment when drums and bass came in. Also sibilants are strong, but very clean, while upper trebles are delicate without brightness. Violins "sing" and trumpets have wonderful "bite". Shirley Horn "You won't forget me" title song with Miles Davis solo sounds great. Same for "It had to be you" with Brandford Marsalis solo.
I put my ear, as close as I could, to the tweeter and it was completely silent. Heat sinks get very warm when playing at high level for extended time, but stay lukewarm at comfortable listening levels. So far AHB2 has only 25 hours of play time, but I expect further improvements to be subtle. To your suggestion about incorporating pink LED I have to say NO (I was awake).
I encountered strange problem at the beginning. My remote stopped working. I tried it with different sets of batteries. I unplugged AHB2 and DAC3 to no avail. After about 20 min it started working again by itself. I thought, that since power timer on AHB2 was set to 40min it could've turn off DAC3 since it works both ways, but now I cannot repeat it - it turns on fine in the morning. I hope it was just a fluke. I'm going to disable this timer anyway (don't need it).