Curious if this is normal behavior: checking the console I see a kernel process, AppleSmartBatteryManager, running its polling for battery diagnostics every 60 seconds. It will initially start a poll, and then immediately restart it, then process its series of command checks. This happens whether the MBP is plugged into the power adapter or not. It occurs on both High Sierra 10.13.6 and Mojave 10.14, and appears on any MacBook so far that I've tested. I am currently running a 2018 MBP i9 config, but also checked on a late 2013 model, and a 2011. Those both had High Sierra. This polling event seems to carry a cpu hit with it that can overload your coreaudio stream.
For background audio streaming like from iTunes, it is a bit more random to get the coreaudio to overload with the battery manager. I think it depends on other background processes just hitting the cpu at the same time. Howver, the problem is really apparent within a pro audio app, like Logic Pro. I can replicate the coreaudio overload nearly everytime the battery manager begins its poll.
If I have a CPU intensive plugin on the active track, Logic appears to assign that processing to the same core that the Kernel processes are running. An easy example is to set your audio device in Logic to the MacBook Speakers, set a 64 sample buffer, and load up a heavy Alchemy patch, Bowed Metal Space usually works well for this, and drop in a Chromaverb defaul fx just to run the active track a bit CPU high. Older systems might not need as much to trigger the issue. Then check your console for when the battery manager is cycling its poll, and start playing a bunch of notes live leading up to the time to trigger the synth. I nearly always get a cpu spike within Logic's performance meter, and then a dropout in the audio creating a short glitch sound. The console log will show the overload event happening right after the battery manager starts its poll. Jusat looking for some deeper insight into this. I'm working with a pro audio hardware company to iron out their latest driver, but the more I dig into this, the more is appears an issue with the MBP and the battery manager.
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17:40:24.007144 -0500
kernel
Starting poll type 2
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kernel
Restarting poll type 2
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Logic Pro X
HALC_ProxyIOContext.cpp:1068:IOWorkLoop: HALC_ProxyIOContext::IOWorkLoop: skipping cycle due to overload
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kernel
Command 0x2 completed. inCount: 2 data:0x5
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coreaudiod
HALS_OverloadMessage.cpp:159:perform: Audio IO Overload inputs: '' outputs: 'BuiltInSpeakerDevice' cause: 'Unknown' prewarming: no recovering: no
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17:40:24.020030 -0500
Logic Pro X
HALC_ProxyIOContext.cpp:1068:IOWorkLoop: HALC_ProxyIOContext::IOWorkLoop: skipping cycle due to overload
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kernel
Command 0x1 completed. inCount: 2 data:0x1001
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Command 0x16 completed. inCount: 2 data:0x40e0
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Command 0x53 completed. inCount: 2 data:0x0
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Command 0x54 completed. inCount: 2 data:0xe443
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Command 0xa completed. inCount: 2 data:0x0
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Logic Pro X
HALC_ProxyIOContext.cpp:1068:IOWorkLoop: HALC_ProxyIOContext::IOWorkLoop: skipping cycle due to overload
default
17:40:24.025972 -0500
coreaudiod
HALS_OverloadMessage.cpp:159:perform: Audio IO Overload inputs: '' outputs: 'BuiltInSpeakerDevice' cause: 'Unknown' prewarming: no recovering: no
default
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coreaudiod
HALS_OverloadMessage.cpp:159:perform: Audio IO Overload inputs: '' outputs: 'BuiltInSpeakerDevice' cause: 'Unknown' prewarming: no recovering: no
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kernel
Command 0xb completed. inCount: 2 data:0x0
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Command 0xc completed. inCount: 2 data:0x1
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Command 0x11 completed. inCount: 2 data:0xffff
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Command 0x3f completed. inCount: 2 data:0x10df
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Command 0x3e completed. inCount: 2 data:0x10de
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Logic Pro X
HALC_ProxyIOContext.cpp:1068:IOWorkLoop: HALC_ProxyIOContext::IOWorkLoop: skipping cycle due to overload
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kernel
Command 0x3d completed. inCount: 2 data:0x10de
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coreaudiod
HALS_OverloadMessage.cpp:159:perform: Audio IO Overload inputs: '' outputs: 'BuiltInSpeakerDevice' cause: 'Unknown' prewarming: no recovering: no
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kernel
Command 0x3c completed. inCount: 2 data:0x0
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Command 0x12 completed. inCount: 2 data:0xffff
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Command 0x9 completed. inCount: 2 data:0x329b
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Command 0x8 completed. inCount: 2 data:0xbe7
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Command 0x17 completed. inCount: 2 data:0x8
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Command 0x13 completed. inCount: 2 data:0xffff
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Command 0xf completed. inCount: 2 data:0x1c8b
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Command 0x10 completed. inCount: 2 data:0x1cc1
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kernel
SmartBattery: finished polling type 2
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coreduetd
CDDBatteryMonitor:
received batterycallback, currentPercentage:99.266404!
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Dock
notifyBestAppChanged:(null) UASuggestedActionType=0 / opts=(null) when=Tue Aug 28 17:40:24 2018 confidence=0 from=/
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17:40:24.893829 -0500
dasd
Rescoring all 127 activities []
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17:40:24.894399 -0500
dasd
501:com.apple.suggestions.harvest:4F97D0:[
{name: DeviceActivityPolicy, policyWeight: 20.000, response: {Decision: Must Not Proceed, Score: 0.00, Rationale: [{deviceActivity == 1}]}}
], FinalDecision: Must Not Proceed}
default
17:40:24.894881 -0500
dasd
501:com.apple.mediaanalysisd.fullanalysis:053C55:[
{name: DeviceActivityPolicy, policyWeight: 20.000, response: {Decision: Must Not Proceed, Score: 0.00, Rationale: [{deviceActivity == 1}]}}
], FinalDecision: Must Not Proceed}
default
17:40:24.895624 -0500
dasd
501:com.apple.KeyboardServices.MigrationTask:01E06D:[
{name: DeviceActivityPolicy, policyWeight: 20.000, response: {Decision: Must Not Proceed, Score: 0.00, Rationale: [{deviceActivity == 1}]}}
], FinalDecision: Must Not Proceed}
default
17:40:24.896186 -0500
dasd
501:com.apple.parsecd.flusher.background:9157F4:[
{name: DeviceActivityPolicy, policyWeight: 20.000, response: {Decision: Must Not Proceed, Score: 0.00, Rationale: [{deviceActivity == 1}]}}
], FinalDecision: Must Not Proceed}
default
17:40:24.896966 -0500
dasd
501:com.apple.bird.cache-delete.push:598505:[
{name: DeviceActivityPolicy, policyWeight: 20.000, response: {Decision: Must Not Proceed, Score: 0.00, Rationale: [{deviceActivity == 1}]}}
], FinalDecision: Must Not Proceed}
default
17:40:24.897456 -0500
dasd
501:PDCardFileManager.CacheMaintenance:A10855:[
{name: DeviceActivityPolicy, policyWeight: 20.000, response: {Decision: Must Not Proceed, Score: 0.00, Rationale: [{deviceActivity == 1}]}}
], FinalDecision: Must Not Proceed}
default
17:40:24.898136 -0500
dasd
0:com.apple.apsd.apprefresh:DD90CD:[
{name: PowerNapPolicy, policyWeight: 5.000, response: {Decision: Must Not Proceed, Score: 0.00, Rationale: [{(inADarkWake == 0 AND appRefresh == 1) AND wakeState == "0x1f"}]}}
], FinalDecision: Must Not Proceed}
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17:40:24.898511 -0500
dasd
Setting timer (isWaking=1, activityRequiresWaking=0) between and for