I have had plenty of D Amps. I have noticed that most D amps seem to need a 1 -2 day burn in to sound right ( to my ears). This is subjective I know.
Its almost like the chips need to "loosen up" . When I first listened to PA7 , I thought it was "broken". I already have the PA5. I am really happy with the PA7 plus at the moment. It took 1- 2 days of continuous play. it seems to still be improving.
D Amps I have owned. Temple audio, Fosi, Topping, Project audio, SMSL
Some D amps increase in volume over first 8 hours. Start the amp at 100% volume. 8 hours later - 50%?
Not sure if anyone has come across this? i always wondered if the "review" copies were "burned in " before being sent out for review.