The Aurender is a complete player. You do need a Ethernet cable connected to the player though. Just load in your DSD or PCM music files and play back with your Android phone or I Pad. It does have built in free internet radio, Tidal and Qobuz you can subscribed to, and MQA you purchase additionally. It will outperform your Mac Mini no matter your mods.
The Matrix X-SPDIF 2 you can check out on this thread.