Hi. I’m following a little that topic and this case with error of A70pro. Seems like it is connected with overheating due to providing relatively high current (mAmpers) to headphones. So if you want to “test it”, take some 50ohm or less planars, with relatively low efficiency (preferably less than 101dB/V or 95dB/mW), turn on high gain and go high with volume (but not to maximum, do not risk to damage headphones with too much voltage!). Among cheap headphones, fostex T50rpIII could be good for such tests or more demanding and expensive headphones like HE6se, HE560. I saw people reporting errors even with DT990pro (low efficiency but high impedance). HD660S2 are easy to drive. Edition XS require some current (very low impedance) but are very efficient so I’m not sure if are good for tests. But, this amplifier A70pro is overkill for most headphones on the market so… it should work flawlessly. I do not even understand why errors are “allowed” by the company - in FAQ there are potential errors and how to deal with it. Why shall I waste my time on products which are put on the market with already known errors?I'm curious what kind of headphones people got, that have experienced the hd dc abnormal error.