Stutter at the beginning of DSD playback using multiple AU plug-ins

Hello… First post from a new Audirvana user, formerly PureMusic user… Pleased to have made the change and VERY satisfied with the sound-quality and the application features, etc… I’m a headphone-centric audiophile…

I use the 112dB “Redline Monitor” AU plug-in implicitly for HTRF to 384kHz and I have DSD files that have been down-converted to 24/352.8k using the BitPerfect “DSD Master” so to audition through Redline Monitor… I up-convert all PCM files to DSD128 with a -6dB gain structure prior to up-conversion, subsequently feeding my TEAC UD-501 DAC…

Being a new Audirvana user, I wanted to experiment and see how the application handled multiple AU plug-ins and I inserted the 112dB “Redline EQ” which is also good to 384kHz, after Redline Monitor… I started playback of a 352.8k file and after a few seconds the playback stuttered slightly and as playback continued, spurious stutters/dropouts continued to occur… I lowered the look-ahead memory to 4Mb and this did reduce the intensity/duration of the interrupts but doesn’t eliminate them… I’m using the DoP 1.1 protocol setting. SoX settings are nominal… using A type 8th-order filter… With the EQ removed, playback is as expected using Redline Monitor alone. Outside of the interrupts, I don’t get tick and pop drop-outs…
(This was an experiment… I don’t generally use EQ with Redline Monitor)
Any insights?
My system:
macOS version 11.2.3 (20D91)
MacBook Pro (15-inch, 2016)
2.7 GHz Quad-Core Intel Core i7
16 GB 2133 MHz LPDDR3

Hello @Agoldnear,

Can you send me a copy of the “Debug Info”? You can get it in Audirvana Settings>General>Debug Info

Note: By clicking on the Debug Info button, Audirvana automatically copies all its content, all you have to do is paste it in response to this message.

Thanks Damien3;

I’ve changed some memory settings and and I’ve also changed the volume-attenuation prior to DSD up-conversion to -2dB, so to work better with my UD-501 FIR setting… Still getting the initial interrupt/stutter at the beginning of playback.

Here’s the Debug Info:

Audirvana Mac Version 3.5.44 (3574)
macOS 11.2.3 with 16384MB RAM

Registered to patrick_doran

SIGNAL PROCESSING:

Polarity Inversion:
	Globally: OFF
	Per track: ON
Effects plugins ACTIVE in offline mode
	AU plugin #0: Effect - 112dB Redline Monitor ()
	AU plugin #1: Effect - 112dB Redline Equalizer ()
	AU plugin #2: None
	AU plugin #3: None

UPSAMPLING:
SoX to DSD128 with filter type A 8th order
SoX filter parameters
Bandwidth at 0dB = 99.5
Filter max length = 30000
Anti-aliasing = 99.9837
Phase = 66

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

LIBRARY SETTINGS:
Sync list: 2 folders
AUTO: /Volumes/FIREWHEEL/High-Resoulution Audio
AUTO: /Volumes/FIREWHEEL/Loud1/iTunes Media
iTunes/Music library synchronization: last synchronized on Tue Mar 16 13:56:26 2021

Library database path: /Volumes/FIREWHEEL/Loud1/AudirvanaPlusDatabaseV2.sqlite

ACTIVE STREAMING SERVICES

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

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

Max. memory for audio buffers: 6026MB

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

Preferred device:
TEAC USB AUDIO DEVICE
Model UID:TEAC USB AUDIO DEVICE:0644:8043
UID:AppleUSBAudioEngine:TEAC Corporation:TEAC UD-501:2111000:1

Currently playing in Integer Mode:
Device: 2ch Non-mixable linear PCM Interleaved 24bits little endian Signed Integer, 8 bytes per frame 352.8kHz

Active Sample Rate: 352.8kHz
Hog Mode is on

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

Selected device:
Local audio device
ID 0x40 TEAC USB AUDIO DEVICE Manufacturer:TEAC Corporation
Model UID:TEAC USB AUDIO DEVICE:0644:8043 UID:AppleUSBAudioEngine:TEAC Corporation:TEAC UD-501:3111000:1

8 available sample rates up to 384000Hz
44100
48000
88200
96000
176400
192000
352800
384000
Audio buffer frame size : 116 to 4096 frames
Current I/O buffer frame size : 512
Volume Control
Physical: No
Virtual: Yes
MQA capability
Auto-detect MQA devices: No
Not a MQA device, user set to not MQA
DSD capability: DSD via PCM 1.1
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 0x41 2 channels starting at 1
24 virtual formats:
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 384kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 352.8kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 192kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 176.4kHz
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 Non-mixable linear PCM Interleaved 32 little endian Signed Integer 384kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 352.8kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 192kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 176.4kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 96kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 88.2kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 48kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 44.1kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 384kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 352.8kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 192kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 176.4kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 96kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 88.2kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 48kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 44.1kHz

32 physical formats
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 384kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 352.8kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 192kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 176.4kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 96kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 88.2kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 48kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 44.1kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 384kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 352.8kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 192kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 176.4kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 96kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 88.2kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 48kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 44.1kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 384kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 352.8kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 192kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 176.4kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 96kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 88.2kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 48kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 44.1kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 384kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 352.8kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 192kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 176.4kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 96kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 88.2kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 48kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 44.1kHz

Local devices found : 3
Device #0: ID 0x36 Built-in Output Manufacturer: Apple Inc. Model UID: AppleHDA:57 UID: AppleHDAEngineOutput:1F,3,0,1,1:0
Device #1: ID 0x40 TEAC USB AUDIO DEVICE Manufacturer: TEAC Corporation Model UID: TEAC USB AUDIO DEVICE:0644:8043 UID: AppleUSBAudioEngine:TEAC Corporation:TEAC UD-501:3111000:1
Device #2: ID 0x2a AutoAggDevice Manufacturer: Apple Inc. Model UID: com.apple.logic.AutoAggDeviceUID UID: com.apple.logic.AutoAggDeviceUID

UPnP devices found : 0

Can you try to disable upsampling in the audio output settings and try to reproduce your issue?

Thanks Damien3;

Ok… I deactivated up-sampling and the file plays as expected…

Re-activated up-sampling to DSD128 and the stutter/interrupt occurs at the beginning of the track… Changed up-sampling to DSD64 and the stutter/interrupt occurs at the beginning of the track…

Using one band of EQ with a very narrow notch filter using an emulation/model… output gain is set for 0.0dB unity…

Here’s the debug file when up-sampling is deactivated:

Audirvana Mac Version 3.5.44 (3574)
macOS 11.2.3 with 16384MB RAM

Registered to patrick_doran

SIGNAL PROCESSING:

Polarity Inversion:
	Globally: OFF
	Per track: ON
Effects plugins ACTIVE in offline mode
	AU plugin #0: Effect - 112dB Redline Monitor ()
	AU plugin #1: Effect - 112dB Redline Equalizer ()
	AU plugin #2: None
	AU plugin #3: None

UPSAMPLING:
SoX not in use
SoX filter parameters
Bandwidth at 0dB = 99.5
Filter max length = 30000
Anti-aliasing = 99.9837
Phase = 66

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

LIBRARY SETTINGS:
Sync list: 2 folders
AUTO: /Volumes/FIREWHEEL/High-Resoulution Audio
AUTO: /Volumes/FIREWHEEL/Loud1/iTunes Media
iTunes/Music library synchronization: last synchronized on Tue Mar 16 13:56:26 2021

Library database path: /Volumes/FIREWHEEL/Loud1/AudirvanaPlusDatabaseV2.sqlite

ACTIVE STREAMING SERVICES

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

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

Max. memory for audio buffers: 6026MB

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

Preferred device:
TEAC USB AUDIO DEVICE
Model UID:TEAC USB AUDIO DEVICE:0644:8043
UID:AppleUSBAudioEngine:TEAC Corporation:TEAC UD-501:2111000:1

Currently playing in Integer Mode:
Device: 2ch Non-mixable linear PCM Interleaved 24bits little endian Signed Integer, 8 bytes per frame 352.8kHz

Active Sample Rate: 352.8kHz
Hog Mode is on

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

Selected device:
Local audio device
ID 0x40 TEAC USB AUDIO DEVICE Manufacturer:TEAC Corporation
Model UID:TEAC USB AUDIO DEVICE:0644:8043 UID:AppleUSBAudioEngine:TEAC Corporation:TEAC UD-501:2111000:1

8 available sample rates up to 384000Hz
44100
48000
88200
96000
176400
192000
352800
384000
Audio buffer frame size : 116 to 4096 frames
Current I/O buffer frame size : 512
Volume Control
Physical: No
Virtual: Yes
MQA capability
Auto-detect MQA devices: No
Not a MQA device, user set to not MQA
DSD capability: DSD via PCM 1.1
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 0x41 2 channels starting at 1
24 virtual formats:
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 384kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 352.8kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 192kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Float 176.4kHz
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 Non-mixable linear PCM Interleaved 32 little endian Signed Integer 384kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 352.8kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 192kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 176.4kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 96kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 88.2kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 48kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 44.1kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 384kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 352.8kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 192kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 176.4kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 96kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 88.2kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 48kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 44.1kHz

32 physical formats
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 384kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 352.8kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 192kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 176.4kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 96kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 88.2kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 48kHz
2 ch Mixable linear PCM Interleaved 32 little endian Signed Integer 44.1kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 384kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 352.8kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 192kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 176.4kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 96kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 88.2kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 48kHz
2 ch Mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 44.1kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 384kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 352.8kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 192kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 176.4kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 96kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 88.2kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 48kHz
2 ch Non-mixable linear PCM Interleaved 32 little endian Signed Integer 44.1kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 384kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 352.8kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 192kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 176.4kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 96kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 88.2kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 48kHz
2 ch Non-mixable linear PCM Interleaved 24 little endian Signed Integer aligned low in 32bit 44.1kHz

Local devices found : 3
Device #0: ID 0x36 Built-in Output Manufacturer: Apple Inc. Model UID: AppleHDA:57 UID: AppleHDAEngineOutput:1F,3,0,1,1:0
Device #1: ID 0x40 TEAC USB AUDIO DEVICE Manufacturer: TEAC Corporation Model UID: TEAC USB AUDIO DEVICE:0644:8043 UID: AppleUSBAudioEngine:TEAC Corporation:TEAC UD-501:2111000:1
Device #2: ID 0x2a AutoAggDevice Manufacturer: Apple Inc. Model UID: com.apple.logic.AutoAggDeviceUID UID: com.apple.logic.AutoAggDeviceUID

UPnP devices found : 0

@Damien3
To add to my last post regarding up-sampling deactivated… I’ve just noticed an approximately 2-3dB output gain when the Redline EQ is inserted as compared to when it is not inline… It would seem this is inconsequential, as I’ve observed that reducing the gain -8dB before up-sampling to DSD does not eliminate the interrupt/stutter… Playback of 16/44.14kHz files with Redline EQ inserted after Redline Monitor that are being up-sampled by power-of-two to 352.8kHz presents no interrupt/stutter.

Have you tried to deactivate real time mode for your plugin?

I’m not familiar with this setting in the plug-ins and I don’t have any such control of the Redline Monitor or Redline EQ… I have never heard of this with a AU plug-in… they all have real-time controls… Obviously, I cannot use any real-time control using DSD up-sampling as described in the Audirvana settings for plug-ins and the real-time control in Audirvana deactivated…

If you are asking if I have had the ‘Realtime control’ activated, I have not been using Realtime control at all… If the debug info is telling you that it is activated, it is giving you wrong information…

Can you make a screenshot of your Audio Unit settings in Audirvana?

I meant the settings of Audio Unit section of Audirvana, not the plugin itself.

Damien3

I’m sure you have an idea as to what is disrupting the flow… I will make a somewhat educated guess in presuming the DSP accumulator/buffer needs more latency before it delivers data-output to the sample-rate converter at these high sample-rates before playback begins? It sounds like a ‘switch’ is being toggled momentarily and causing a hiccup/dropout… It seems that some memory allocation or a system-level operation is short on resources or is being taxed or instigated unexpectedly, robbing resources… As you can determine from the debug information, my MacBook Pro (touch-bar) has plenty of horsepower to run the operations… It just seems to me the operations need more memory or latency to fill the buffer before playback starts… After the initial interrupt, playback is as expected until the next interrupt occurs after a few more seconds, and after that interrupt, the file continues to play as expected until the next little interrupt occurs, and so-on and so-forth, until the file playback has completed. To plainly state this, playback is “hiccuping” at these sample-rates, when inserting Redline EQ after Redline Monitor… Otherwise to restate, the system works as expected when Redline Monitor is the only AU plug-in running.