Just got the Fostex HP-A3, it's such a nice product, best ever audio product I've bought! The headphone/line out switch, volume knob control, and complete silence of preamp really really greatest I've ever heard, and I'm shocking surprise it run via my phone OTG cable straight away with enough power to drive my Shure SRH1540, with balanced sound output. Recommend you guys to buy, one thing though is this unit does not have remote control