2017 MBP Sleep Issues with USB-C Monitor / Hub

[MCusuma1]

I have a 2017 non-touchbar MBP with a Samsung SH850 USB-C monitor I just purchased. Everything works great when the computer is on and I'm using it. However when I put it to sleep, the monitor tries to go to sleep after a few seconds, and then I hear the "blonk" sound on the computer as if I had just plugged in the power, and the screen comes on black for a second, then goes back off. Then the process repeats itself, every minute or so.

When putting to sleep with the lid opened, I noticed that when this happens, the laptops internal screen says "100% Charged". The issue does not occur if the battery is still charging (not at 100%).

This also seems to disconnect the USB hard disks I have connected to the monitor's USB hub, as when I wake the system from sleep I see a ton of "Drive not disconnected / ejected properly' notifications on the right.

I also tried shutting down, and the monitor seemed to turn the computer back on all by itself!

I tried reinstalling a fresh copy (full erase) of High Sierra last night with no luck.

HELP!

 

[chscag]

Welcome to our forums.

It sounds like problem is with your USB-C monitor's hub. Unless any USB-C adapter or hub is approved by Apple, there is no guaranty that it is compatible with your MacBook Pro. The Samsung monitor itself might be OK but it sure appears the USB-C connector-hub is the problem. I would return the monitor if you can and look for something else.

 

[Raz0rEdge]

The monitor is powering the laptop and charging it, thus the various indications. My guess is that there's a bug in the monitor firmware dealing with the laptop going to sleep, since at this point the data stops and the monitor goes into sleep mode on its own and likely cuts power. But then it seems to begin providing power again and the laptop is going through its charge indication, where it will wake up momentarily, but likely not long enough to show anything.

This theory is further aided by the fact that you see the USB device disconnection happening which would be the case when the data is not longer being sent to the laptop when the monitor goes to sleep.

You are at the bleeding edge of this sort of connectivity and likely suffering the bugs associated with it.

For this sort of connection, Apple only recommends the LG UltraFine 5K monitors because Apple and LG worked together to make it work properly. So likely this issue doesn't exist there and it might take a little time for others to cover all the various combinations (though this sleep like a huge oversight on Samsungs part since going to sleep is not so out of the ordinary use of laptops).

Do you put your laptop to sleep by closing the lid or choosing Apple Icon->Sleep from the top menu bar?

 

[MCusuma1]

Thanks for the replies! So far this is the only forum out of four including apples official support community where anybody has bothered.

I put the computer to sleep through the Apple menu.

I was really hoping this display would work out, I have been through three docks and two usb-c to DisplayPort cables with my old qhd monitor (hp zr2740w) but had constant sleep issues there as well.

Apples official displays with lg seem nice but are very expensive

 

[Raz0rEdge]

Technically using the Apple menu should be the same as closing the lid, but can you try closing the lid instead to sleep the MBP and see if things behave as they should. After closing the lid, open it up again and see if you get the disconnection messages.

I've been using a HooToo USB-C hub with HDMI out and a BenQ 27" monitor that has been working great.

The LG monitors are indeed quite expensive, but what you get is a "Apple tested" combo that should just work.

Anywho, try the closing the lid method and report back on any changes you see in the monitor/MBP behavior.

 

[MCusuma1]

So I tried your suggestion and the behavior was the same.

Here is a clue from the Power Management log:

2017-10-24 18:45:43 -0400 Assertions Kernel Idle sleep preventers: IODisplayWrangler
2017-10-24 18:45:43 -0400 Notification Display is turned on
2017-10-24 18:45:44 -0400 Wake DarkWake to FullWake from Deep Idle [CDNVA] due to UserActivity Assertion: Using AC (Charge:100%)
2017-10-24 18:45:44 -0400 HibernateStats hibmode=3 standbydelay=10800 16
2017-10-24 18:45:44 -0400 Kernel Client Acks Delays to Sleep notifications: [AppleBacklightDisplay driver is slow(msg: SetState to 0)(983 ms)] [AppleIntelFramebuffer driver is slow(msg: WillChangeState to 1)(982 ms)] [AppleHDADriver driver is slow(msg: SetState to 1)(415 ms)] [AppleHDAHDMI_DPDriver driver is slow(msg: SetState to 1)(476 ms)]
2017-10-24 18:45:45 -0400 PM Client Acks Delays to Wake notifications: [com.apple.duetactivityscheduler is slow(303 ms)] [sharingd is slow(536 ms)] [PowerChimeAgent is slow(1203 ms)]


The line in bold is definitely the culprit. If I could hack MacOS to stop charging at 99% I believe the issue would be solved, as it would never reach this "Charge:100%" state. Is there a way to do that?

 

[MCusuma1]

So I have another major update: this issue only occurs when I tell the computer to go to sleep, whether via the Apple menu or the "Sleep" button on the login screen. If I allow the computer to fall asleep via the sleep timer, the issue does not occur.

Therefore it would seem this is an issue with the computer or OS and not the monitor.

 

[Raz0rEdge]

Well that's range strange since all of those should yield the same sleep behavior and thus the same outcome. I don't believe there is a way of limiting the charger to go to a certain amount within the OS. There might be 3rd party apps that support that.

 

[ferrarr]

Is there a power switch for the monitor only? Turn the display off, and let the Mac take care of itself. The only thing I do, sometimes, is put on my screensaver, before I leave it.

 

[MCusuma1]

Is there a power switch for the monitor only? Turn the display off, and let the Mac take care of itself. The only thing I do, sometimes, is put on my screensaver, before I leave it.

Hi! Thanks for the suggestion. I thought of that; unfortunately when the monitor is turned off, the external hard disks are disconnected and the laptop stops charging.

I have an appointment with the genius bar on Saturday, and also have an RMA for the monitor. If I can't get it working I'm seriously considering getting a used LG Ultrafine 4K (really want the 5K but have sticker shock...).

 

[kg90]

Hi! Thanks for the suggestion. I thought of that; unfortunately when the monitor is turned off, the external hard disks are disconnected and the laptop stops charging.

I have an appointment with the genius bar on Saturday, and also have an RMA for the monitor. If I can't get it working I'm seriously considering getting a used LG Ultrafine 4K (really want the 5K but have sticker shock...).

I have the exact same problem that you describe in this thread and is very curious if you found a solution for it?

 

[Essentia]

Happened to find this thread a few years later and have this exact same problem with a 2019 MBP and a Samsung S80UA 27 in 4k monitor.

When the MBP falls asleep on its own, no problems. However, if I initiate sleep, it goes through the "power notification" > back to sleep cycle endlessly.

Here's to hoping that by 2022 someone has found a reliable fix for this!

 

[howardc64]

M1 MBP 13" with Samsung LS27A600UUNXGO (QHD USB-C monitor w/HUB)

this wakeup behavior seems to be caused by a lightning cable plugged into a USB-A port on the HUB. Once cable removed, seems no more wakeup while sleeping.

 

[Raz0rEdge]

You're saying that just having a lightning cable plugged in without a device plugged in was causing a wake up? I have a cable plugged in a hub that is connected to a switch which connects to either my MBP or Mac Studio and when either of those Macs goes to sleep, the cable doesn't wake it up.

The wake event is pretty explicit

• Wake on alarm
• Wake on network
• Wake on wired/wireless keyboard & mouse activity
• Wake on lid opening for notebooks

 

[howardc64]

You're saying that just having a lightning cable plugged in without a device plugged in was causing a wake up? I have a cable plugged in a hub that is connected to a switch which connects to either my MBP or Mac Studio and when either of those Macs goes to sleep, the cable doesn't wake it up.

The wake event is pretty explicit

• Wake on alarm
• Wake on network
• Wake on wired/wireless keyboard & mouse activity
• Wake on lid opening for notebooks

I should describe my "wake" issue more clearly and might need more testing to see the behavior deterministically (don't yet know how to reproduce deterinistically)

- When I put M1 to sleep, USB-C monitor will go to standby in a few seconds after
- USB-C display would periodically display no USB-C input. Presumably it has come out of standby. No M1 image was displayed so its unclear if M1 woke up.

So its more monitor waking up rather than Macbook.

I had lightening cable and fitbit charger plugged into the USB-C monitor's HUB but neither was connected to the device. So I've pulled all of these and see if the above behavior changes.

 

[ferrarr]

- USB-C display would periodically display no USB-C input.

My ViewSonic monitor shows that occasionally as well. It has nothing to do with the Mac. If you disconnect the USBC cable, the monitor will display that message as well.

 

[howardc64]

My ViewSonic monitor shows that occasionally as well. It has nothing to do with the Mac. If you disconnect the USBC cable, the monitor will display that message as well.

Thanks! I'll definitely check this behavior and follow up with confirmation.

 

[Raz0rEdge]

All monitors (and TVs) will show you a "No signal", "No input" or some variation when the source goes away. They'll also go into power-save mode shortly after too.

 

[howardc64]

A bit more observation. Behavior is exactly as in post #1

1. MBP goes to sleep, monitor goes to standby soon after
2. Eventually will hear MBP power plug-in sound, monitor wakes up black for a few seconds, flashes USB-C no signal, goes into standby again.
3. After some delay (1min?) does #2 repeatedly

No USB accessories plugged into the monitor. MBP and USB-C monitor connected by 1 USB-C cord for charging and video.

Doesn't seem to do this right away after manually put MBP to sleep but eventually #2-#3 loop starts. This doesn't occur with my DELL S2718D USB-C monitor. Looks like Samsung USB-C monitor in standby is powering down then power on charging to the MBP and wake up the display briefly before detecting MBP isn't providing any video signal and returns to standby. Mirrors this post ( link ) Maybe Samsung USB-C monitor is cutting off USB-C power when no display for a period. Instead, it should keep USB-C power on to supply power to the MBP.

Unfortunately work around is to manually power off monitor everytime goes to sleep (MBP will also not be charged then but not a big issue) Power off sequence is button press + down arrow + button press so a bit more cumbersome than desired. No firmware update available for this Samsung USB-C monitor ( LS27A600UUNXGO )

 

[Jimmysb]

A bit more observation. Behavior is exactly as in post #1

1. MBP goes to sleep, monitor goes to standby soon after
2. Eventually will hear MBP power plug-in sound, monitor wakes up black for a few seconds, flashes USB-C no signal, goes into standby again.
3. After some delay (1min?) does #2 repeatedly

I have been changing my sleep setting of late due to a different issue, but with power to my monitor on, my Mini sleeps, then some time later the monitor comes out of stand-by (monitor orange light goes white), but I get the no activity box on the monitor and goes back to stand-by. It would seem the Mini is still asleep, but something has woken the monitor. I just power down the monitor overnight now.