Hi doc.
It's one of those things that almost becomes 'mental'. Now that I have heard this, I am constantly listening for it.
To answer your questions though - I have not had the opportunity to sample with other material yet, so it's just been the radio City blu-ray with the Dolby HD track. Volume is not excessive - running avout -30db, my usual range for movie watching - which equates to about 80 dB. With my ear next to the tweeter I turn it down to preserve my hearing!
Clipping should not be an issue. Also, it's a new Pio SC-05 which has the digital ICE amp so should not distort anyway. it's not a hiss or buzz, more 'scratchy' as you put it.
