MacBook Pro 2017 15" > OS X 10.14.5 > Roon Build 416
Network Details (Including networking gear model/manufacturer and if on WiFi/Ethernet)
Audio Devices (Specify what device you’re using and its connection type - USB/HDMI/etc.)
Pro-Ject Pre Box S2 via USB
Description Of Issue
Hi. This has been hounding me for days and I’m out of ideas. The issue is control over audio output. When I begin a track in Roon, the Audio MIDI Setup switches from the Pro-Ject S2 USB output to the Mac Built-In Output. This also changes the format setting…for example from 352.8 Hz to 44.1 Hz (on a 24/352 track). For the duration of time music is playing, no effort can move the sound back to the S2 output…but as soon as the music stops it moves back automatically.
Any ideas on how I can keep the Audio MIDI Setup selection on S2 DAC permanently?
I’ve posted a 15 second video on youtube for viewing. The switch happens at 5 seconds in.
For MQA to decode/render properly, playback needs to be bit perfect. ‘Exclusive Mode’ enabled helps this…
So you’ll have to choose which one you want - either Roon bit perfect playback (and MQA decoding/rendering properly) with ‘Exclusive Mode’ enabled, or adjusting Audio MIDI with ‘Exclusive Mode’ disabled. Can’t have both unfortunately.
I appreciate the feedback but I’m challenged to believe that 32/352.8 resolution tracks (or even 24/192) must be attenuated to 44.1, 88.2, or 96 Hz before outputting via USB to the S2 DAC, which can play up to 32/768 resolution.
In simpler terms, the Mac Audio MIDI is hijacking my bit-perfect high resolution signal and quashing it. The sound is negatively affected. The S2 DAC is Roon certified. I have to believe this is a problem others have experienced and solved.
The Pro-Ject S2 does perfectly fine with Roon and PCM32/768k and DSD512 (I’ve used both).
When you say 32/353 tracks, do you mean MQA 353kHz tracks? If so, which track/album specifically?
If you have ‘Exclusive Mode’ disabled then yes. So just leave ‘Exclusive Mode’ enabled and no app should be hijacking your Roon playback.
What’s the problem you’re having with ‘Exclusive Mode’ enabled? Is it just that you can’t adjust the same rate in Audio MIDI? That’s attempting to hijack. ‘Exclusive Mode’ enabled helps to prevents you (or macOS/apps) from hijacking the audio during Roon playback - this is a good thing.
My recommendation is to leave ‘Exclusive Mode’ enabled if you want MQA to decode/render properly… and even with non-MQA playback too…
The problem with Exclusive Mode is (I believe) actually a problem with the Mac OS X. Essentially, my Mac is hijacking the exclusive connection between Roon and the S2 DAC, sending the signal to “Built-In Output”, attenuating it to lower sample rates, and then outputting to the DAC.
If you view the video, you’ll see at 5 seconds in the switch from S2 DAC 352.8 Hz to Built-In Output at 44.1.
To clarify this issue a different way; when playing music via Roon (in Exclusive Mode) I can’t select any output except Built-In Output. Built-In Output is selected automatically as soon as the music starts (you can watch it switch in the video) and while the music is playing, there is no way to choose the S2 DAC as the output.
And yes, disabling Built-In Output in the Roon software has no effect.