Mac Mini as a music server

@wtf +1
I used a Mac Mini with all the mentioned software too. Audirvana+ was my fav, but between the Apple updates you already explained and A+ trouble with library files getting periodically corrupted, it was frequently not allowing me to just sit down & listen when I  wanted it most. I tried a jillion USB cables from cheap to $1k Lightspeed. I tweaked with iFi filters, Schiit Wyrd decrapifier and some double-headed cables to separate the power leg from the signal leg. It all made some difference, but was ultimately unsatisfying.
Moving to a  Sonore microRendu with a good linear power supply, Synology NAS and Lumin app on iPad is in a completely league. Better sound by far, better reliability with less maintainence and a comparable friendly user interface. 
A much clearer optional  future path with Roon compatibility, HQ Player NAA, and hardware upgradeability all make it feel like a good investment. From the day of the first Mac O/S update, I was counting the days until my Mini became obsolete. Cheers,
Spencer 

Sure, but when you turn automatic updates off, security updates aren't installed. If streaming or internet radio are part of why you use the Mac, you become more vulnerable to attack every day. You get annoying prompts daily suggesting updating. Most updates bloat the OS with crap neutral or detrimental to audio playback. ITUNES never goes away and it opens every time you load a disc even just to rip it. 

My trouble with Audirvana+ mostly boiled down to library indexing hidden files getting screwed up. This causes library appearing totally gone when it really isn't (scary!). Support is by one smart busy guy in France...replies are friendly but take a while. The fix usually entailed finding hidden files, deleting them, reinstalling, then reloading library which took almost a day for me with about 3TB of music at the time, connected directly to a Lacie Firewire drive, not across a network. It wasn't the worst audio trauma I have dealt with, but why bother?!!
Cheers,
Spencer