iPhone better than Wiim Mini (in my system)

For a bit now, I’ve been streaming with an iPhone going into a Marantz CD6006 CD Player via its USB going into a Schiit Modi 3 via optical. I’ve been running things this way because the Marantz’s analog output has gone wonky.

All the conventional wisdom has stated that a standalone streamer going into a DAC will yield better results than a phone going into a DAC.

So just for giggles, I ordered a Wiim Mini and tried it out. It was going directly into the Schiit Modi. The USB on the Marantz only streams from Apple devices so I couldn’t do an even comparison with the Wiim going into the Marantz nor did I have a cable for the phone to go directly into the Modi.

My findings: The iPhone-Marantz-Modi chain was superior to the Wiim-Modi. The Wiim-Modi setup had more dirt in the sound with less well defined images as well as dull uncentered bass. The iPhone-Marantz-Modi setup was more clear, articulate and defined.

I trust my ears and heard what I heard. So my question is: Is the Marantz+Modi combo adding a degree of filtering not possible with the Wiim-Modi combo? Why does the Marantz setup sound so much better?