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superamit

macrumors member
Original poster
Mar 9, 2011
36
30
Brooklyn, NY
I have a MacBook Air M1 (16GB/1TB) connected to a Samsung 4K TV as a primary display using a USB-C to HDMI adapter.

When the MacBook Air goes to sleep and I wake it, the TV reports receiving no signal, and the MacBook doesn't seem to "see" the display any longer.

Power cycling the TV doesn't help. Unplugging the USB-C to HDMI cable doesn't help. Holding down Option and clicking "Detect Displays" in Display Preferences doesn't help. The only way to get the display recognized again seems to be restarting.

I used this same cable, adapter, and display with my 2020 MacBook Air (also running Big Sur) and it didn't have any issues waking from sleep.

Anyone run into a similar issue or have a suggestion on how to resolve it?
 

Zazoh

macrumors 68000
Jan 4, 2009
1,510
1,116
San Antonio, Texas
In power settings check the option for Prevent computer from sleeping automatically when display is off.

Then when display goes to sleep try re-waking. This won’t fix, but it will determine if monitor or computer. Because it it wakes, it actually is the MBA.
 

CSBBody

macrumors member
Jan 23, 2020
60
44
I am having this same issue now, i have “replaced” my 16” with the MacBook Air M1 and hooked up my dell 3818 and when it goes to sleep, and i try wake it with external keyboard and mouse, the screen doesn’t wake.

Even if i lift the lid, the laptop screen is still “cropped” but nothing to the dell, which is connected directly via thunderbolt 3 as always. Only solution is a system restart and then work.

I had the same issues with my MacBook 16 when i first got it, and cant remember the workaround, or if an update fixed it.

I checked my settings now, and i see the option for Prevent computer from sleeping automatically when display is off, is checked off.
 
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superamit

macrumors member
Original poster
Mar 9, 2011
36
30
Brooklyn, NY
I'm using "CHOETECH Type-C to HDMI Adapter 6FT 60W PD Powering Cable Thunderbolt 3 (4K@60Hz)"

 

Spheniscidae

macrumors newbie
Nov 26, 2020
1
0
Same issue on M1 MacBook Air with an LG 32UD59-B. Now I can't get it to show up on the monitor at all. I left it overnight and when I woke up this morning I couldn't get the display to wake. When I open up the MacBook it has a strange cropped resolution and I can only see the top left corner of my screen. After restarting the MacBook screen is normal but it still won't recognize the monitor 9 times out of 10. Super frustrating.
 

ucsbdude

macrumors newbie
Jul 16, 2002
1
1
Same issue for me. I have an M1 Mac Mini and my 4 year old 4K acer will not come back on after the computer has been put to sleep for a while. Hooked up a new 4K acer as a second monitor and it comes back on just fine every time but the older one will not come back until the computer is rebooted.
 
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KShopper

macrumors member
Nov 26, 2020
84
116
I have a problem if I put my MBA to sleep with the external display connected, then wake it later without the display connected. The screen real estate becomes larger than the physical laptop screen. So I can't see the bottom Dock bar, unless I hover over it then I can barely see the top of the zoomed icons.

Only fix was a reboot.

If I disconnect the screen and then put it to sleep no issues.
 

AlexOnBoard

macrumors newbie
Nov 26, 2020
9
16
I use MBP and had the same issue once without connection to power adopter.

However, this not happens after connect to the power adopter. tested around 10 times.
 

Jasonondesign

macrumors newbie
Nov 30, 2020
18
3
northampton ma
Same

I've been running my prior-generation 13inch Macbook Pro (2019 4 USB-C ports) in clamshell mode for over a year now without a problem, but with my new 13in MBP M1 (16GB/1TB fully patched Big Sur 11.0.1) the monitor keeps disconnecting.

  • Sometimes it works for a while, then cuts out.
  • Sometimes it won't connect at all in Clamshell and I have to leave the Mac open to get it to work at all.
  • Sometimes I have to unplug it 3-4 times to get it to work.
  • A couple of times it worked for a few hours without problems.
  • It works sometimes when not plugged in to power, and sometimes when it is.
  • Once when it wasn't working I noticed that the computer wasn't charging, so I unplugged the USB-C power and plugged that back in. It started charging but still wouldn't connect to the monitor.
Things I've tried to troubleshoot
  • I've restarted (duh)
  • I've reached out to support a few times. The first few people tried to get me to reset my NVRAM, which you can't do manually on the M1. They're going to get back to me about this, but the guy I talked to said he's heard about it in his briefing and apparently "it's a thing".
  • I restarted in "safe mode"
  • I have tried with two different HDMI adaptors (Apple Multiport, and a 3rd party one).
  • I've tried three monitors (LG 34.5inch (2560 x 1080), LG 29 inch 2k (1998 x 1080), and ViewSonic 2k (1998 x 1080).
Other comments about:
 

arn

macrumors god
Staff member
Apr 9, 2001
16,363
5,798
I posted a separate thread on this.

---

I have the M1 MacBook Pro and it's closed-lid connected at my desk to a 38" Dell monitor via USB-C with a USB keyboard off the monitor. This was the same setup I had with a 16" MacBook Pro.

Since switching to the M1, I've had some issues with the Monitor not waking up. The computer seems on. When I open the lid, sometimes the monitor kicks in. Other times I have to unplug and replug the USB-C. Occasionally them monitor will work, but the external keyboard won't function.

----

Hopefully something that can be fixed in a software update?
 
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jdb8167

macrumors 601
Nov 17, 2008
4,749
4,466
Same issue on M1 MacBook Air with an LG 32UD59-B. Now I can't get it to show up on the monitor at all. I left it overnight and when I woke up this morning I couldn't get the display to wake. When I open up the MacBook it has a strange cropped resolution and I can only see the top left corner of my screen. After restarting the MacBook screen is normal but it still won't recognize the monitor 9 times out of 10. Super frustrating.
I have a similar but different problem with a 24" 4K LG 24UD58-B with my M1 MacBook Air. USB-C to Display Port almost never works and even when it does, it rarely works after waking from sleep. Luckily my USB-C to HDMI adapter seems to work somewhat more reliably.

The new problem that I’m seeing with the HDMI that is that sometimes (it's happened 3 times in the last week or so) I get a completely distorted fast flickering black and white display. The only fix is to unplug the USB-C to HDMI adapter and wait until the MBA goes to sleep. Then I can wake it up again by plugging the HDMI cable back in and it usually works.

Frustrating but it has all the signs for buggy display drivers. I'm sure Apple is hard at work fixing things.

Edit: Left out an important detail.
 
Last edited:

Carrotcruncher

macrumors regular
Oct 13, 2019
184
150
Same issue here MacBook Air M1, Secondary Display not detected after wake , only solution is a restart, I have contacted the seller of this device and will be returning, it, the issues I have encountered are way too many for the price, will be replacing it with one of the Intels that's currently on sale for a bargain price.
 

djlythium

macrumors 65816
Jun 11, 2014
1,139
1,592
Yep, happening with my M1 MBP connected to a Samsung Q50 32" 4K via usb-c to HDMI.

Waking from sleep only really works if the M1 hasn't been able to go into 'deep sleep', meaning it hasn't been 'asleep' for a long time, like overnight. In such a case, unplugging the usb-c side, logging in from wake, then replugging in the cable works.
 

Jasonondesign

macrumors newbie
Nov 30, 2020
18
3
northampton ma
I've noticed maybe a trend where the problem showed up after I played some Heroes of the Storm (Blizzard, I know, bad people), and immediately afterward the Google Drive Backup and Sync app crashed. I'm wondering if other people on this thread are using (or not using) Google Drive, and/or if they run any apps which take over full screen and have independent resolution controls (i.e. go into game options and adjust resolution).
 
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superamit

macrumors member
Original poster
Mar 9, 2011
36
30
Brooklyn, NY
I'm having the problem regularly and I'm not using the Google Drive or Backup and Sync app, nor am I using games or other apps that change my screen res.
 

Jasonondesign

macrumors newbie
Nov 30, 2020
18
3
northampton ma
I also have problems with the M1 "forgetting" what resolution my external monitor is.
Latest is Apple Support asked me if I have a custom background image, and I do, so they asked me to remove the custom background image and use one of the default Big Sir background images. I'm trying that now, but just wanted to shout out in case there's a trend.
 
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RossGGG

macrumors newbie
Aug 9, 2011
20
17
I have the exact same issues others have reported here with an HP z24x G2 display. Hopefully an OS update can fix this.
 

proalorrs

macrumors newbie
Nov 12, 2020
11
1
Reddit says try this
I had the same issue, I had to change to DP setting on my monitor from 1.4 to 1.2. Now the monitor wakes up from sleep without an issue.

hope that works. My m1 will arrive soon and I have the same setup ... fearing this pain in the neck
 

Alfred wong

macrumors newbie
Jan 29, 2020
3
3
hong kong
I also have this issue. I thought that it would be my computer issues and found help in the Apple store.
However, it just works when they connect my computer with their LG 5K ultra fine display.

I tested my display with the 2016 MacBook pro and 2020 Intel MacBook air and they work properly with the same usb-c cable.

Hope that this issue would be fixed with a software update.
I also posted the issues on apple community: https://discussions.apple.com/thread/252130686
 

superamit

macrumors member
Original poster
Mar 9, 2011
36
30
Brooklyn, NY
Reddit says try this
I had the same issue, I had to change to DP setting on my monitor from 1.4 to 1.2. Now the monitor wakes up from sleep without an issue.

hope that works. My m1 will arrive soon and I have the same setup ... fearing this pain in the neck
Interesing! Mine is connected via HDMI so I don't think there's a way for me to change DP settings to make it work.
 

Jasonondesign

macrumors newbie
Nov 30, 2020
18
3
northampton ma
Reddit says try this
I had the same issue, I had to change to DP setting on my monitor from 1.4 to 1.2. Now the monitor wakes up from sleep without an issue.

hope that works. My m1 will arrive soon and I have the same setup ... fearing this pain in the neck
I don't know what DP settings are, but I also have HDMI.
 

jdb8167

macrumors 601
Nov 17, 2008
4,749
4,466
OK yeah that makes sense. I don't think there are many settings other than pressing option to "detect display" and that doesn't seem to detect it.
The DP settings on the monitor. Theoretically the ports support Display Port 1.4 but the suggestion is to test DP 1.2 by setting it on the monitor.
 
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