Arcam RDAC/Mac Mini 24/96 not playing

Connection with external Audio Devices
1

I am running a late 2014 Mac Mini, OS Catalina, an Arcam RDAC over USB and Tidal Hifi.

I can play at 24/96 over optical no problem at all but over USB it maxes out at 88.2 before going all distorted and garbled (high pitched prickly popping).
I have tried the following -
A new QED high speed USB lead
A new power supply for the RDAC
Trying all the USB ports and ensuring everything else is unplugged
Integer mode and non integer mode
All of the various permutations of MQA settings
Sys opt mode on or off
Updating the Os (latest version as of 27/1/20)
Updating Audirvana (as above)

I’m at a loss really as I feel I have tried everything, I can’t help feeling this is a software issue as the RDAC has no issues at all over optical.

I love the sound but it’s left me a bit miffed that I can’t max out the capabilities of the DAC. Having said that the imaging and separation of MQA tracks is mind blowing, I’m hearing instruments I’ve never noticed before. I’ll never go back to iTunes…

2

I have the same DAC and with 24/96 it works without issues over USB (same OS and Audirvana version). The issue must be related to MQA files. I will test that and let you know how it goes.

3

Audirvana Mac Version 3.5.29 (3559)
macOS 10.15.2 with 4096MB RAM

Registered to xxxxxxxx

SIGNAL PROCESSING:

Polarity Inversion:
	Globally: OFF
	Per track: ON
Effects plugins NOT ACTIVE

UPSAMPLING:
SoX not in use
SoX filter parameters
Bandwidth at 0dB = 99.5
Filter max length = 30000
Anti-aliasing = 100
Phase = 66

AUDIO VOLUME:
Max allowed volume: 100
Replay Gain: None
SW volume control: OFF

LIBRARY SETTINGS:
Sync list: 0 folders
iTunes/Music library synchronization: last synchronized on Wed Jan 1 15:35:18 2020

Library database path: /Users/bowcall/Library/Application Support/Audirvana/AudirvanaPlusDatabaseV2.sqlite

ACTIVE STREAMING SERVICES
TIDAL: Connected as HIFI

=================== AUDIO DEVICE ========================

CoreAudio audio path, buffer I/O frame size: 512

Max. memory for audio buffers: 1024MB

Local Audio Engine:
Exclusive access: Enabled
Integer mode: Enabled

Preferred device:
ARCAM DAC
Model UID:ARCAM DAC:0C56:0002
UID:AppleUSBAudioEngine:ARCAM:ARCAM DAC:14100000:1

Currently playing in Integer Mode:
Device: 2ch Non-mixable linear PCM Interleaved 24bits little endian Signed Integer, 6 bytes per frame 88.2kHz

Active Sample Rate: 88.2kHz
Hog Mode is on

Bridge settings:
Sample rate limitation: 88.2kHz
Sample rate switching latency: none
Limit bitdepth to 24bit: OFF
Mute during sample rate change: OFF

Selected device:
Local audio device
ID 0x29 ARCAM DAC Manufacturer:ARCAM
Model UID:ARCAM DAC:0C56:0002 UID:AppleUSBAudioEngine:ARCAM:ARCAM DAC:14400000:1

5 available sample rates up to 96000Hz
32000
44100
48000
88200
96000
Audio buffer frame size : 29 to 4096 frames
Current I/O buffer frame size : 512
Volume Control
Physical: No
Virtual: No
MQA capability
Auto-detect MQA devices: No
Not a MQA device, user set to not MQA
DSD capability: Unhandled
Device audio channels
Preferred stereo channels L:1 R:2
Channel bitmap: Ox3, layout:
Channel 0 mapped to 0
Channel 1 mapped to 1

Audio channels in use
Number of channels: 2
Use as stereo device only: No
Simple stereo device: Yes

1 output streams:
Number of active channels: 2, in 1 stream(s)
Channel #0 :Stream 0 channel 0
Channel #1 :Stream 0 channel 1

Stream ID 0x2a 2 channels starting at 1
10 virtual formats:
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 96kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 88.2kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 48kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 44.1kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 32kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 96kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 88.2kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 48kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 44.1kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 32kHz

10 physical formats
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer 96kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer 88.2kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer 48kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer 44.1kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer 32kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 96kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 88.2kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 48kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 44.1kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer 32kHz

Local devices found : 3
Device #0: ID 0x35 Built-in Output Manufacturer: Apple Inc. Model UID: AppleHDA:88 UID: AppleHDAEngineOutput:1B,0,1,2:0
Device #1: ID 0x40 HDMI Manufacturer: Apple Inc. Model UID: AppleHDA:88 UID: AppleHDAEngineOutputDP:1B,3,1,2:0:{2D4C-0DF6-01000E00}
Device #2: ID 0x29 ARCAM DAC Manufacturer: ARCAM Model UID: ARCAM DAC:0C56:0002 UID: AppleUSBAudioEngine:ARCAM:ARCAM DAC:14400000:1

4

I see that you have the sample rate limitation set to 88. This is most likely the issue.

5

Yeah, that’s to stop it trying to play on 96 where the issue starts. If i set to 96/unlimited it just crackles.

6

Have you tried with non MQA files in that resolution?

7

Yes, same result when upscaling 44.1 to 96. It’s weird because it’s only in USB.
To be honest I’m happy with 88.2 as it sounds amazing, just confused as to why USB it can’t handle 96.

8

I just tried with my rDAC and it works perfectly with 24/96, both plain PCM and MQA from 2L.no.

It must be either an issue with the DAC or with your setup. I’m running Mac Version 3.5.29 (3559) on MacOS Mojave.

You can try to play the files with different app, like VOX or something.