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Full Version: 2018 Mac Mini to Devialet via USB
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Is anyone using a 2018 Mac Mini to connect to their Devialet via USB? Or thinking of doing so?

There is a serious problem in this scenario and I currently would not advise anyone to buy a 2018 Mini for use with their Devialet.

Basically, Apple's implementation of USB2 is currently flawed and audio glitches occur.

It is currently not completely clear whether this is a hardware or software problem but in my opinion it is software. 
There is a hardware workaround involving an (expensive) Thunderbolt 3 HUB.

I will post more information if anyone is interested.
Why do you want to do this? I assume your Devialet is connected to your router via Ethernet and you could attach your Mac Mini to your router in the sane fashion or, like me, communicate via WiFi.
(21-Feb-2019, 13:11)Gerronwithit Wrote: [ -> ]Why do you want to do this? I assume your Devialet is connected to your router via Ethernet and you could attach your Mac Mini to your router in the sane fashion or, like me, communicate via WiFi.

Yes, I could easily connect using AIR over ethernet.

I don't because -


1) I don't like the delay introduced by AIR. I prefer the ZERO delay using USB.

2) I record, using Audacity, audio coming from the Devialet using  bi-directional USB. This does not work properly if you send via AIR and receive via USB. It only works well if you send  via USB and receive over USB. I have never been able to figure out where the problem lies, Apple? Devialet? Audacity? So I use USB

3) I also don't like the way AIR takes over the volume of the Mac but that is just a personal foible.

For me there is no audible improvement in using AIR so I am perfectly happy to use USB


I should have mentioned that the problem outlined above applies to any recent Mac with a T2 chip, not just the Mini.
I'm interested in the technical details, yes. Thanks.
Since the iMac Pro in late 2017, all Macs include an additional chip, the T2.
Apple initially said this was for security reasons but they have also transferred a lot other processing from intel to the T2.

They have transferred USB audio to the T2 (maybe they have transferred ALL USB and ALL Audio processing, I don't know)

The problem seems to stem from trying to keep time synchronisation between the Intel chip and the T2.

Approx. every 30 minutes a process called 'timed' runs to find out the exact correct time from Apple's servers. If the exact time on the Mac doesn't match the Internet time, things get re-synced. This can cause the unix kernel to stop and immediately restart the audio system, resulting in a brief glitch in sound over USB.

You can simulate this glitch by toggling on and off System Preferences -> Date & Time -> Set Date & Time automatically

If you have a Thunderbolt 3 Hub, connect the Devialet to a USB2 port on the hub and the problem goes way. All the USB2 processing is in the hub, the Mac is talking Thunderbolt to the hub so the processing is different.

More info

https://www.forum.rme-audio.de/viewtopic...66#p136666

https://appleinsider.com/articles/19/02/...face-users

https://www.head-fi.org/threads/what-a-l...t-14790143

https://forums.macrumors.com/threads/do-...i.2153841/
Thank you very much for sharing the information.
I was really surprised when l read this post, as until now I’ve never noticed or had any problems with my 2018 mini. So of course I paid a little more attention this past weekend and yes, every 30 minutes or so there is, at least in my set up, an ever so slight “hiccup”...... in playback! Maybe I’m lucky, in other people’s systems it may be worse but to my ears it’s not a big deal!
I grew up with vinyl, and when I think back to those days, the pops, cracklings, repeatable loops and such l wouldn’t want to change my system at all, l love my digital files and playback, even if it’s not 100 % perfect ?