Thanks for reading and for your feedback. What were your different preferences? I'm new to headphone amps so always interested to hear different perspectives.
Also, what cans are you using when you checked for noise? I.e. what's their impedance and sensitivity (or just model and I'll look up the specs)?
See you at A2A sometime!
Where we differ is filter settings: I settled for #4, which is totally flat at 96kHz sampling, and to me sounds smoother than #6. Also prefer the energy of high gain, even though it compresses the soundstage a bit. I use the Q701 so the soundstage is quite big anyway. They are 105 dB @ 62 ohm. Being quite bright they should carry the white noise through, if there was any.
Is it possible that the noise is generated by the source rather than the amp? Do you still get it if the source is disconnected?