Intermittent quiet pops when using EQ plugins in Audirvana Plus

[Cloud9Blue]

Ok, so I picked up a new Audio-GD NOS just recently, which is significant step up from my old HRT Music Stream II+.  But with the increase in resolution, I can now hear a faint  random popping sound every now and then, which is particularly noticeable in music with high dynamic range.  
 
Played around with setup (buffer size, forced upsampling, etc.) and also tried to bypass Audirvana completely by using AU Lab to run the VST plugin instead, but the problem still persists.  Using TDR Nova at the moment, since it is free and the 4 band parametric filter is adequate for my EQ need.  Tried a whole bunch of other plugins too, including the popular BMG Equilibrium, but still the same problem with all of them.
 
Playback is completely noise free if I don't turn on any of EQ plugings, but LCD-2 rev. 2 just sound so sublime with a bit a treble bump up top.  
 
Playback is done from a late 2013 Macbook Pro Retina (2.4 GHz Core i5, 8 GB ram, 256 GB SSD HD), which should be more than adequate...  Kind of running out of ideas to try here, so I am hoping a pointer or two from you guys.

 

[Cloud9Blue]

Hummm, alright, guess no one knows anything about this...

 

[PleasantSounds]

Just a guess, but if you're boosting the highs in EQ it is possible that they distort.
If that's the case then try lowering the lower frequencies and leaving highs at 0.

 

[Cloud9Blue]

Just a guess, but if you're boosting the highs in EQ it is possible that they distort.
If that's the case then try lowering the lower frequencies and leaving highs at 0.

That's not the problem.  Highest EQ I have is 3dB, hardly anything.
 
Anyway, the issue is solved with using optical output on my mac instead of USB.  I believe the post processing causes some clocking or mortherboard noise with the USB.