Hmm, now why does this sound good...

Anyone else out there own a recent vintage Samsung monitor with headphone jack included? I'm surprised how good this models headphone output sounds using Roon over HDMI connection vs listening to USB connected DAC /headphone amp to same PC. It's a 2014 model, wondering if anyone else care to opine on their experience with like or later gear https://pcmonitors.info/reviews/samsung-s24d390hl/