DisplayPort connected monitor periodically wakes up when system is sleeping
I have a new MacBook Pro (13-inch, M1, 2020) running BigSur 11.4 (20F71) and I have an LG 4K flat panel connected to the laptop via DisplayPort using a Thunderbolt to DisplayPort adapter. When I put my MBP to sleep (not power down), the 4K monitor keeps powering on and off again. When the MBP is actively running, there are no issues with the display. This happens with both an LG 32UD60-B and LG 32UD59-B. I have disabled all notifications that can popup when the MBP is sleeping, disabled Wake for network access and removed legacy (x86) apps that like to periodically wake up and check the status of things. The MBP’s screen will not turn on however (not unless I wake up the MBP).
I have been reading about this issue with Big Sur and DisplayPort connected external monitors. I have tired several different Thunderbolt to DisplayPort adapters and a hub with a built-in DisplayPort interface (the CalDigit TS3 Plus) but the behavior remains the same.
The monitor does come up properly when I wake up the system, so I'm not experiencing the "black screen" issue that other users using DisplayPort connected monitors have reported.
I am filing this under Big Sur since it seems that others have had very similar issues with Big Sur on older x86 Macs.
Thanks for any help!
MacBook Pro 13″, macOS 11.4