Trouble with Mac Mini playback

[Jim Madeira]

Help please
Audio playback is fuzzy and not sharp and clear after tracks has been playing for a minute or so. Something not right? My system is:
Pure Music 3 used as downloaded plus PM streamthrough as downloaded
Mac Mini 2011, i7, El Cap
AMD RadeonHD 6630M,
HRT Microstreamer,
Paradigm Millenia One CT.
iTunes on external La Cie HD Firewire 800
All audio cables by Audioquest
Tracks mix of 256 and Apple lossless from CDs
Route is from La Cie to Mac Mini to HRT to Paradigm.
Any suggestions gratefully received.

 

[wilsonlaidlaw]

I have improved my Mac Mini a whole lot by adding an M2Tech HiFAce2 reclocker with USB to Coax conversion, earlier this year. The original reason to do this was that my Aqua Acoustic La Voce DAC, that I have in France, was made for me to the wrong spec with only a 48kHz/16bit USB input. Aqua were less than helpful about correcting this.

With the HiFace2 reclocker, I could use the Coax input to the DAC, which was up to 192kHz/24 bit, although the Mac Mini struggles at anything above 96/24. My Mac Mini travels backwards and forwards with me between France and the UK as my media server.

When I got back to the UK, my Mac Mini normally connects through the USB to an Audiolabs M-DAC, with the Lakewest FW upgrades. I tried it with the USB direct against the HiFace2 output from another USB socket and switching backwards and forwards between the two inputs from the Mac Mini on the DAC (USB and Coax). The HiFace to my surprise (USB to HiFace then via Coax to DAC), was noticeably better than the USB at 96/24 straight to the DAC. I think this shows that although the 2011 onwards versions Mac Mini were supposed to have reduced jitter, there must still be quite a lot. Reclocking it with the HiFace2 reduces the jitter to insignificant levels (it has 2 high precision Quartz oscillators). I bought it direct from M2Tech and they sent it out very quickly. http://www.m2tech.biz/it/commerce/?mod=new I have no connection with them other than being a satisfied customer.