is it worth repair or stick with the PT-100 I have at the moment?
Pt100 sounds better
Transport: Sony BDP 5100 Blu ray player spdif PC using Musiland Digital Times WASAPI via BNC connection - DAC: DC-1->XLR XPA-1 , RCA->Basx A-100 CD: Denon DCD 600 PCM 61 DAC. RCA Amp: XPA-1 gen 2 using XLR connections. Speakers: Axiom Audio m80 V3, Sennheisser HD700 headphones. two pairs 12 guage each bi-wire speaker cables per monoblock Headphone amp: Basx A-100 (INCREDIBLE VALUE!!)
Other equipment: Asus Xonar essence ST Behringer UCA 202 Sennheiser HD600
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.