Willy,
You’re getting some non-optimal advice here. People are right that you should NOT use a cheap switch. Nor should you use an optical on one and USB on the other. Neither will provide a valid comparison.
Pick 5 to 10 tracks that you feel are very well recorded and that you really enjoy. Be sure to include some acoustic instruments and vocals that you’ll recognize as sounding “real” or not. Some complex rock is fine too. Be sure to include some cymbals and kick drum or bass drum.
Listen to the entire group and listen for specific things on specific tracks such as cymbal strikes, sibilant voices, deep bass, transients, handling of complex passages, clarity, soundstage depth, width, specificity, etc. Take notes on how “real” each track sounded and of course, whether you found it emotionally involving. Did it make you want to keep listening a lot longer or did you find yourself wanting to do something else?
Then go through the same group with the other streamer, hooked up EXACTLY the same way. Go through the whole process 2 or 3 times.
Quickly switching back and forth between pieces of equipment within the same track seldom tells you whether you want to live with a new piece of equipment or not.