Amp: XPA-1 gen 2 using XLR connections. Speakers: Axiom Audio m80 V3, Sennheisser HD600 headphones. two pairs 12 guage speaker cables per monoblock for biwire. Headphone amp: Basx A-100 (INCREDIBLE VALUE WITH HD600s!!)
Keep in mind also the "bathtub curve of reliability." The DAC is old enough now that it may be entering its "wear out phase" where failures increase almost exponentially. Even if you get the current problem repaired, other components may also be about to fail.