Agreed Currawong I have now soldered the DAC HDAM's ground wire to the RCA jacks ground.
I haven't noticed anything (when unplugging the H/Amp power connector from the main pcb) other than the voltage regs on the main pcb are now quite a bit cooler than before.
Sennsay...thanks man !!! It's been a crazy 24 hours around here
Peete.