Had exact same problem, and the exact same solution worked...from the outside like you said.  Thanks!

  Sennheiser HD600, HRT Musicstreamer II, Schiit Magni and a beat up Pioneer SACD/DVD-A player.

You got me on Ghosts...that's indeed good work.

Just finished listening to it and honestly, I think this is just another in a long line of very average albums put out by NIN.  I haven't felt that Trent has made a solid album since TDS, with the exception of "Still".  The Fragile has some excellent songs on it but it was a bloated double album...

Finally have a bit of time and am listening now to the audiophile WAV.  Was really surprised that there is such a small difference between the two versions, at least as far as dynamic range goes.   Sounds pretty clean.  I haven't listened to the regular version yet, though.  ...

Quote: I use freshly charged 1.2V NiMH.  The amp will blow your brains out with the HD25's.  Just not enough power to properly run the 600.  

Quote: No distortion, but doesn't reach a high volume.  I can get a bit more volume before distortion using the little amp, but nowhere near what I get using HD25 loud and clear.

If you can drive em with your PA2V2, I must be doing something wrong.  I think I've tried every gain position on the amp / computer volume combination.  My system is foobar2k (wasapi event) --> music streamer ii --> PA2V2  --> HD600.  I listen to FLAC exclusively, many at 24/96.  I've tried...

Got my HD600s in today, a step up from the HD-25-II that I've owned for a couple of years now.     Unfortunately, I cannot yet power this thing as I only have a portable PA2V2.  Listening at low levels is all I can do at this point until my Magni comes in next week.  At volumes I normally...

Had similar problems with mine.  Dropping the buffer to 50 fixed it for me as well.

Quote:     Thank you.  It's the PA2V2.  Just got it in yesterday.

Picked up a PA2V2 and a set of HD25-1 II headphones last week for my first step into this madness.  Loving both the amp and the cans.  Got both for just under $200USD.  Great investment.