macOS Sequoia 15.5 - Deep sleep issue (standby 1): RTC/Host wakes, 10-13W power consumption

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macOS Sequoia 15.5 - Deep sleep issue (standby 1): RTC/Host wakes, 10-13W power consumption

Hello everyone,

I have a Mac mini M2 Pro (2023 model) running macOS Sequoia 15.5, and after the recent update, I'm experiencing issues with it achieving or maintaining deep sleep.

Goal and Pre-Update Behavior:

My goal is for the Mac mini to enter deep sleep with minimal power consumption (around 1-2W) after I manually put it to sleep at night. I prefer to manually put it to sleep (pmset -a sleep 0). Before the update, this worked as expected.

Current Post-Update Issues:

When I manually put the Mac mini to sleep, during the night it either wakes up and stays in a higher power state (10-13W), or it doesn't enter deep sleep at all and gets stuck in this state. This behavior persists even after disconnecting all external USB storage devices (including my USB flash HDD).

My current pmset -g settings:

Other Steps and Findings:

I've used the Terminal command sudo pmset schedule cancelall to cancel all pmset-managed scheduled tasks. The pmset -g sched command now shows no scheduled events.

Wake logs (log show) indicate:
- Wakes due to rtc/Maintenance (e.g., NUB.SPMI0Sw3IRQ nub-spmi0.0x02 rtc).
- Wakes due to Host (0x01) from AppleTopCaseHIDEventDriver (these wakes persist even without the USB flash HDD connected, so the source might be another HID device or an internal issue).
Sleep prevented by assertions for processes like runningboardd, coreaudiod, bluetoothd, sharingd, powerd appear in the pmset -g output after waking or when trying to sleep.

My Questions:

Has anyone else experienced similar issues (inability to achieve/maintain deep sleep, wakes followed by high 10-13W power consumption) on a Mac mini M2 Pro (2023) or other Apple Silicon Macs after updating to macOS Sequoia 15.5?
Why would the Mac not return to deep sleep after nightly rtc/Maintenance or Host (0x01) wakes, or why would it not enter it at all, even with standby 1 and sleep 0 set? Could the update have affected timers like standbydelay or the behavior of processes preventing sleep?
What diagnostic steps would you recommend to determine why the Mac isn't entering/staying in deep sleep, and to address issues with processes like runningboardd, coreaudiod, sharingd preventing sleep, especially if Host (0x01) wakes are not tied to external USB storage?
Are there any known power management regressions in macOS Sequoia 15.5 for M2 Pro chips?

Thank you.

Mac mini, macOS 15.5

Posted on May 16, 2025 3:18 AM

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Answer 1

Top-ranking reply

hatatitlaaa Author

Level 1

26 points

Jun 16, 2025 1:12 AM in response to hatatitlaaa

Quick update on my Mac mini M2 Pro (macOS Sequoia 15.5) sleep issue:

I've discovered that my Apple Studio Display seems to be the key factor.

When the Studio Display is connected, the Mac mini initially deep sleeps at 1-2W for about an hour.
After that hour, something triggers it, and the Mac mini's power consumption jumps to 10-13W (screen remains off) and stays there.
If I completely power off the Studio Display (using a smart plug) after putting the Mac mini to sleep, the Mac mini remains in its 1-2W deep sleep state indefinitely.

This strongly suggests an interaction issue between the Mac mini and the Studio Display, possibly related to Thunderbolt communication or USB activity from the display, which started after the Sequoia 15.5 update. The Mac mini itself seems capable of deep sleep if the display is not 'active' in any way

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Answer 2

BDAqua

Level 10

250,247 points

May 16, 2025 3:25 AM in response to hatatitlaaa

In Activity Monitor, show all procceses, power, anything showing preventing sleep?

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Answer 3

tbirdvet

Level 6

16,988 points

May 16, 2025 4:32 AM in response to hatatitlaaa

This cannot address the root cause but so many uses are having issues when using the sleep function that most now recommend to never use sleep. Just have the display turn off after a preset time or shut the Mac down completely.

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Answer 4

steve626

Level 6

13,539 points

May 17, 2025 12:04 PM in response to hatatitlaaa

You have changed settings in various ways ... what happens if you restore the default settings for pmset and whatever else you have been tweaking? Remember that when an OS update occurs, sometimes some settings won't work the same way that they did before.

Most users don't routinely use sudo pmset and maybe for good reason.

Do you have sharing going on all the time over a network? That might be causing interference with deep sleep. Also, do you have headphones or other devices (aside from external drives) connected? Do you have a dock or moniter or other devices connected? Any of those can keep a Mac from sleeping in the way you expect. And with a new version of MacOS, their interaction with the MacOS may change.

Finally, why does it matter how many watts are being consumed during sleep. Apple may have changed the way computers handle sleep with the latest update. That may be normal and unavoidable. The Mac mini is connected to power at all times. Why does 10W versus 1-2W matter. What problem is this "issue" creating, other than worrying you? But what is the true harm associated with this behavior?

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Answer 5

hatatitlaaa Author

Level 1

26 points

May 17, 2025 3:03 AM in response to hatatitlaaa

Thanks for the advice. I'm just frustrated because it worked perfectly until the last update. Despite other settings, it now sleeps for about 1 hour, but then it stays in a state consuming 10-13W. Previously, it would normally consume 1-2W and would wake up with a click of the mouse or a key press.

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Answer 6

Owl-53

Level 10

101,737 points

May 17, 2025 9:07 AM in response to hatatitlaaa

Regarding your " Wakes due to rtc/Maintenance (e.g., NUB.SPMI0Sw3IRQ nub-spmi0.0x02 rtc). "

From a well respected Contributor

The "RTCReporting_messageLog" file found on Apple devices, such as iPhones and iPads, is a log file related to Real-time Communication (RTC) activity, specifically audio and video calls

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Answer 7

hatatitlaaa Author

Level 1

26 points

May 27, 2025 8:48 AM in response to hatatitlaaa

Thanks for the replies. Sure, keeping the Mac fully on or shutting it down are valid options, but if the system offers sleep mode, I’d like to use it the way it used to work. In the past, my Mac would go into sleep with a power draw of just 1–2W, which was great. Now it’s sitting at 10–13W, which doesn’t exactly feel “green.”

Yes, in absolute numbers it might seem negligible. But when you multiply that by the number of Macs and hours per day, it adds up, especially when it’s something that used to work properly and efficiently. So it’s not just about saving power, it’s also about the fact that something broke that used to work just fine.

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