It looks (in my case) ,that the onboard switching power supply + 5.65V / -5.6V, which supplies the output analog circuits (3 OA) behind the DAC, fails / does not start ..). That PSU is powered from 5V inputs. The all other onboard sources (3.3V, 1.2V, 1V) start up normally, they are linear (not switched) sources, powered by 5V inputs. It is simply a faulty (unreliable) internal symmetrical switching power supply, consisting of one miniature 12-pin IC ( marked DP0 3V4) and a pair of SMD components (2 inductors, diodes, a pair of resistors and capacitors
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