I have a trusty old Apogee Mini-Me pre-amp/compressor with drivers that don't work with anything beyond Windows XP.
For a time, I got away with using it via SPDIF through my trusty old Egosys U2A - it's a cheap little USB Audio Interface which amazingly has both optical and SPDIF ins and outs and cost me less than $100 about a hundred years ago. (I know! Right?)
Basically, the U2A was doing nothing to add to the sound beyond passing through one digital source to another digital source.