I was so disheartened to plug in my new Nothing (1) Headphones into my OP-Z/OP-1 and no sound came out... but it worked fine with my Pocket Operators/EP-1320... I was baffled 🤷 After trying several different setups, settings, etc. I was about to give up when I saw the Ground Loop Isolator I had recently bought and honestly thought I wasted my money because I figured I'd never need it for my recording setup, but I plugged it into my headphones and I could hear sound! 🙌 I am now one happy camper ⛺