Well i can tell you highperf audio first of all gets more quiet, and i am not sure what the highperf part of it is.
Volume_Boost is noticeable, it brings HP audio up enough and is a nice boost of HP off
playing Making of Cyborg with HP off, volume_Boost at 1 and Play Music EQ set to suit my ears my HFI-780 produce a pretty nice sound, considering this is a phone and not a dedicated audio device.
Exactly what I didn't want to hear bout high performance, prob more dynamic range?? Why else would it get quieter?
At least volume boosts works, well see if it actually works over a2dp. Not thinking it will.....
Sent from my Galaxy Nexus