Network time synchronization causes audio overloads

Originator:ricciadams
Number:rdar://46918065 Date Originated:
Status:Duplicate of 45462730 Resolved:
Product:Audio Product Version:
Classification: Reproducible:Always
 
I've been having random audio overloads on my new 2018 MacBook Air. After browsing several logs, I noticed that IOAudioEngine::pauseAudioEngine() was called immediately after the 'timed' process attempted to synchronize the local time to a network time server.

This issue is 100% reproducible and persists across reboots. While audio was playing, I opened up Date & Time preferences and repeatably toggled the "Set date and time automatically" check box. Each time I turned this setting on, I saw a log entry for IOAudioEngine::pauseAudioEngine(). These pauses are often long enough to cause an audio overload.

Steps to Reproduce:
1) Have a MacBook Air 2018 and an audio device whose "Clock Source" isn't "Default". I used both an Apogee Groove and a Focusrite iTrack Solo.
2) Turn on "Set date and time automatically"

Expected Results:
No audio overloads, glitchless playback

Actual Results:
Whenever "Set date and time automatically" is first turned on, or once per hour when 'timed' runs, audio glitches due to something calling IOAudioEngine::pauseAudioEngine() at the kernel layer.

Version/Build:
10.14.2 (18C54)

Configuration:
2018 MacBook Air + Apogee Groove 

Test matrix:
2015 MacBook Pro + Built-in Output = ok
2015 MacBook Pro + Audioengine D3  = ok
2015 MacBook Pro + Groove          = ok
2015 MacBook Pro + iTrack Solo     = ok

2017 iMac Pro + Built-in Output = ok
2017 iMac Pro + Audioengine D3  = ok
2017 iMac Pro + Groove          = ok
2017 iMac Pro + iTrack Solo     = ok

2018 MacBook Air + Built-in Output = ok
2018 MacBook Air + Audioengine D3  = ok
2018 MacBook Air + Groove          = FAILED
2018 MacBook Air + iTrack Solo     = FAILED

Comments

Output from console: https://gist.github.com/iccir/d464c727bbb8a2ba655f106565d50faf

By ricciadams at Dec. 22, 2018, 10:44 a.m. (reply...)

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