What do you mean? A70 Pro is an amp, where did you put the isolator exactly? Isn't it the DAC's fault...Unrelated, but just had to put my galvanic isolator (HS02) on my A70 Pro as my speakers started purring when watching an F1 stream. It fixed it, kinda weird that there's no isolation on such an expensive DAC though.
Ok, I've got my new unit, just tested it with the DT990 250ohms (the one that crashed my last unit), tried it in both low and high gain at -1db (so extremely loudly), the amp is reacting nicely so far, no problem handling everything I throw at it yet.
Now I can enjoy without it without a problem, might have to buy a balanced dac tho, as well as a XLR cable for my Edition XS, but I wont rush things anyway.
My new unit passed through pre-testing on Audiophonic's part tho, so it might not be resolved for everyone, but I'd give them a thumb up there.