I used the CAD script with HQPlayer back in the (10.9 Mavericks) day.I have a headless 2011 Mac Mini as an alternative/ redundancy to my streamer. It may be worth looking at the CAD website to get the script for shutting off unnecessary bits of OSX going on in the background
For those who don’t want to subscribe to Audirvana etc, don’t need streaming and for those (like me) who utterly loathe iTunes and it’s heirs and successors, Swinsian is a very good looking, efficient and cost effective player that does lossless well. And the sound quality is very good.
The USB out to a decent DAC (I use a modified Meridian 518) is a much better solution IMO than the mini toslink.
This is not to pee on people’s chips if they like iTunes/Apple Music, just to offer an excellent alternative that doesn’t suffer from periodic brain farts/database corruption.
EDIT - the CAD script mentioned above is to prepare for an Audirvana installation, but I found it works with Swinsian for me. Do read the cautions and implement at your own risk!
Put ‘computer audio design osx disable’ into Google and the page is the first result.
Do note that it has only been tested up to Yosemite 10.10.2, iTunes 11.1.2 and Audirvana 1.510.
It's best to install in a dedicated machine.
https://www.computeraudiodesign.com/computer-setup/