Greetings everyone, it sure was one heck of a job reading through this entire thread... yet it made the waiting for my very own Zero DAC/amp much more bearable. I ordered my Zero from Lawrence when I was still only somewhere around page 200 of this humongous thread and only read about his failing quality control when it was too late...
My Zero arrived yesterday morning and from the get-go I heard there was something amiss with the sound, every time I turned the volume control on the Zero I could hear distortion, but only in the left channel. Figuring it probably had something to do with headamp section of the unit I first checked if my ALPS pot (which Lawrence had installed) was properly grounded, which it was. After that I decided to check if there was no distortion if I used the RCA-outs connected to my integrated amp... the distortion did not pass. This was somewhat odd, because now the distortion (still only in the left channel) appeared when I turned the volume control on my integrated amp.
Undaunted I unseated one of the LT1364 which were used in the headamp section and put it in the DAC section instead of the HDAM. After listening for a short while through my integrated amp I could no longer detect any distortion when I changed the volume (because I've got no spare opamps I naturally couldn't use the headamp section as well). When I was about to reinstall the HDAM I noticed that some of the wires of the extension wire weren't soldered quite properly, so I set out to resolder those few wires which didn't seem to have been done properly.
Now I tried again, with the repaired (or so I hoped) wire... but still the distortion was apparent. Getting kind of desperate I then tried to free the HDAM from the encasing, to which it was stuck with some kind of dual-sided adhesive tape and after some work with a knife and a flat screwdriver I succeeded in doing so. Now I could plug the HDAM directly into the socket without the need of the extension cable, and what did you know? No more distortion in the left channel while changing the volume! Be it with the volume control on the Zero itself or with the one on my integrated amp.
Thinking I was out of the woods I set out to spend some quality listening time with this DAC/amp, but sadly I was mistaken... Because after some time listening I noticed that there sometimes were slightly audible 'pops', which sounded somewhat akin to the sound you hear when the needle of an element passed a bit of dust on a vinyl record or, I would guess, to the sound of a small electrical (static?) discharge. Strangely enough these still only occurred in the left channel.
And ultimately it is this that I want to pose you all a few questions about.
Of course, the general question would be: what is causing this? Could it be that in my heroic
attempts to free the HDAM from the case might have damaged it? Could it have been damaged because some of the extension wires weren't connecting properly to the module? Or could it be something entirely different, like the grounding of the HDAM? Or maybe a miscellaneous problem unrelated to the HDAM?
Any help at all would be much appreciated and I'm already planning to order one or two new modules straight from GD-audio itself including a better extension wire, but would like to postpone such things if I can get the sound coming from the Zero working properly.
PS: I appreciate you reading that large post... if indeed ye did not scroll past it!
