True.even some of my IEMs sounds dull w/o 16db ticked and vol knob turned above 2-3pm to hear it right. one con though imho, woud've been a 3 step boost than 2.....like 0-8-16db. if this is addressed on the E12DIY silver it's a mass welcome! not sure JamesFiiO and his team thought of this. technically feasible but maybe cost cutting involved as they need 3 way sw, enclosure's extra cut and some additional components to add that feature!!! (maybe $5-10 a piece?) kinda bitter question to match at this price tag. :D
My hardest to drive IEMs (150ohm/95dB RE-262) are unbearably loud at 2-3PM, even without the 16dB boost.
I hope you use a very weak source, because otherwise you need to consult a specialist.