Jitter is the important effect on sound quality here. The lower the jitter, the better the SQ. Also, the playback software can affect the SQ.
If you want a really low jitter S/PDIF coax feed, consider an Ethernet renderer like the Interchange if you have a router or switch nearby your rack. You can use any computer to drive the renderer and any playback software that supports Deezer. Maybe Linn Kazoo?
https://www.audiocircle.com/index.php?topic=156409.0
Cost: around $3K
To improve the S/PDIF output of the Bluesound, you can add a Synchro-Mesh reclocker and a good BNC coax cable to reduce jitter to 8psec. I use one of these with my Sonos to make it world-class.
https://www.audiocircle.com/index.php?topic=157348.0
Cost: around $1K
Steve N.
Empirical Audio