I still think that you can try an UpTone ISORegen and a LPS1.2 (for USB) and a linear power supply for your MacMini [via an UpTone MacMini DC-Conversion / Linear Fan Controller Kit (MMK)] and you should be very satisfied with the results. Not just there yet but pretty close and definitely more analog sounding than now! Just my 2 cents!
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Amp: BAT VK-655SE
Pre-amp/Digital: exaSound e32 w UpTone JS-2 Power Supply; SOtM tX-USBultra w UpTone LPS1.2; Apple Mac Mini w UpTone DC Conversion Kit & UpTone JS-2 Power Supply; Squeezelite w Logitech Media Server 7.9.0
Speakers: Triangle Magellan Cello II
Cables: AudioQuest WEL XLR, AudioQuest Everest, AudioQuest Hurricane HC, AudioQuest NRG-1000, AudioQuest Diamond USB
Rack: Solid Tech Hybrid
Tweaks: Omicron Stabilizzatore Armonico & Gold Evolution SE; IsoTek Sigmas GII w Optimum EVO3; Furutech FT-SWS (R) AC Outlet; Synergistic Research Blue Quantum Fuse