But a phono pre amp??
I responded because you stated that using the MKII without a pre limits your system to a single source, which is false. You additionally stated that it will not allow one to use a CD player which is also false. No, you cannot connect a phono pre with only analog outputs, but you could use a PS Audio NuWave Phono Converter.
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Good points… I mis spoke… Thank you. 
However, we are no closer to identifying the static issue I am having when using the MKII as a pre-amplifier per the owner’s manual, which is running via XLR to my Classe’ Delta Stereo amp. When I swap back to the MKI, this goes away entirely… Hmm… Still trying to troubleshoot…
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When you have the Mk1 in the system, do you have its output set to High or Low?
If you normally use Low, switch it to High and let us know if you hear any static then.
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There is no static with the MKI, only with the MKII, which does not have a high and low gain setting. The only setting in the MK two is switching the single ended output to balanced in the settings menu.
In my case, I am running balanced out of the MKII tot he Classe Delta amp.
UPDATE – Just switched to SE outputs from the MKII to the Classe’ Delta amp and the static is literally 95% gone. Probably due to the less gain offered. But progress. But damn, I feel like its a bit less detailed… Hmm… But oh man, so good.
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Well you didn’t answer my question (did you have the MkI using Low or High?) but OK.
What about ground lift options in the Mk2? Have you tried changing that setting on the outputs while using the balanced connection?
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Just call them when they open up after Christmas and get a replacement. You’ve tried the obvious things and they didn’t work so let them deal with it.
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Tested both High and Low settings with the MKI.
Went through each ground lift setting on the MKII…
Yea, will do for sure… Just wanted to make sure it was not something I was doing or missing.
Had a buddy who has the same unit and says it does it to him on certain amps.
As you’ve verified that your XLR cables are good via the MK I don’t know what else you could do. May just be a bad solder joint on an input jack on the Mk II or farther up line if it does it on both inputs though it shouldn’t do it on either one. Anyway their issue to deal with on a new unit.
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If there’s no static when using single-ended cables, then there’s nothing wrong with the input terminals on the DAC.
James, from what I have read about your amp I think it’s a single-ended design anyway. I say that because they recommend shorting two pins of the XLR input if you’re not using it, and a fully balanced design would never do that.
If the distance from your DAC to amp isn’t especially far you might find you’re happy with the right set of single-ended interconnects.
Yea. I’m reading that now as well. Static is still there slightly, but with the low voltage of the single ended outputs of the MKII it’s hardly audible. Jump the single ended outputs of the MKII to the 4v and it is similar to that of the balanced outs. Interesting for sure. But none the less RCA out of the MKII to the Classe amp is acceptable for now. 
Might be that the circuit which converts balanced input to unbalanced signal in the amp isn’t happy with the level of HF noise coming in.
Interesting thought. I wouldn’t think there would be any HF noise coming from the Air Lens with its isolation. And also the isolation built into the MKII. SHOULD, theoretically eliminate any noise, no?
Ah - no.
The DAC architecture being used here is kinda niche, and like all engineering it involves trade-offs. In exchange for its unusually good audio band fidelity we have to tolerate a non-trivial amount of ultrasonic noise being present on the analog outputs. That’s the inescapable consequence of being a 1-bit (or 1-trit depending on how pedantic you want to be) converter.
This noise ideally just gets low-pass filtered by the normal operation of amps and speakers, but sometimes it causes trouble. There was a fairly dramatic discovery after the first batch of MkII DACs went out to customers that the noise was having an unexpected interaction with a set of internal relays which implemented some variable output attenuation (-10dB, -20dB, -30dB IIRC) that was intended to help with this exact problem. While the attenuators worked overall, the ultrasonic noise was internally reflecting from the relays themselves leading to distortions which were audible in the human hearing band. The whole variable attenuator scheme had to be dumped and the original boards recalled.
So I’m suggesting that something similar to this might be happening with the balanced input circuitry on your amp. If I’m not mistaken about the way your amp is designed, the single-ended input bypasses that little circuit and avoids the creation of audible noise/distortion caused by the ultrasonic components of the signal produced by the DAC.
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The problem with that fine-sounding theory though is that it didn’t happen with your Mk1. Hmmmm.
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Original boards were not recalled for replacement. They removed the relays and returned the units to the customer.
Very interesting.
Thank you for the feedback and thoughts.
A couple updates.
I switched to the single ended outputs and on normal settings the “static” is pretty low and not audible from the listening position, but can still be heard at the speaker. Change the single ended output to the balanced setting (4v) and it is identical in sound and volume to the initially reported static from the balanced outputs. All running direct to my Classe delta stereo amp.
Also,
If I integrate a pre amplifier into the chain (doesn’t matter which one, as I have many) this entire issue disappears. So it seems to be isolated to when the MKII is being used as a pre amp… I have a discord friend who shares that he has had the same experience.
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