Best USB port on a late 2012 Mac mini

Except that my Mac Mini is a late 2016 the setup is the same as gryphongraph’s. But I use Ethernet to deliver the Roon stream to an ultraRendu with LPS 1.2 and Ayre QB-9 DSD DAC. Could I get the same sound quality by going direct from the USB port of the Mini to the Ayre DAC, perhaps with a UBC isolator although I think Ayre USB DACs are thought to deal effectively with jitter? Mini USB direct to Ayre DAC would be neat if it works.

I think my Mac Mini is actually a late 2012, with SSD and external HD. I moved the USB cable to the Ayre DAC from the ultraRendu to the Mini. Roon immediately displayed the DAC as the output device. The setup is balanced analog from the Ayre DAC through a Parasound JC 2 preamp to a pair of JC 1 monoblocks that drive KEF LS50s augmented by a pair of KEF KC62 subs. Audio quality with this setup is excellent.

The list is given below

• Thunderbolt port (up to 10 Gbps)
• FireWire 800 port (up to 800 Mbps)
• Four USB 3 ports (up to 5 Gbps)
• HDMI port.
• SDXC card slot.
• Gigabit Ethernet port.
• Audio in/out.
• IR receiver.

Probably the best thing you can do for your Mac Mini is to upgrade it to a linear power supply.  This does require some modification to the unit.  Here's a very good option:

https://uptoneaudio.com/products/mac-mini-dc-conversion-linear-fan-controller-kit-mmk

Then get a linear power supply of your choice, but make sure that it's a 12V linear power supply that provides at least 4.5 amps of current.  Many of the popular linear power supplies are limited to 2 or 3 amps.  The Keces P8 is an excellent choice.  Or you can go for a Teradak from ebay/china.

+1 on LPS. I use the Uptone MMK with JS-2 LPS, also only critical services enabled. Modded mac mini in entirely different league from stock mini. Do thunderbolt to ethernet conversion for direct ethernet out for another nice improvement, much better than usb out.