I faced the same issue few days back after being able to successfully close the laptop lid with my external monitor connected all the while. For me it started working back after connecting the power cord to the laptop. Without power, laptop does not seem to mirror the display to the external monitor with the lid closed. hope this helps. On a machine as powerful as an m1 it's not a problem. Display link works much better on the mac than it seems to on windows, I have never once had the displays not get detected and have to unplug and replug the dock. Dell also have a ud22, which is a hybrid display link and raw usbc dock. So even without display link it should work well. Open System Preferences > Displays. Click the Arrangement tab. Do not select the Mirror Displays tickbox (unless you want the second screen to show the same content as your original screen). Drag superamit. 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 To bypass the crappy monitor speakers, and output to a decent sound system, I have: 1. USB-c connection from Ipad to Display port connection on monitor 2. 3.5mm earphone lead out of monitor to 3.5mm input - to a external sound system 3. Works! - Volume control - And much better sound quality. Hope this helps others Regards Martin The details: 1. Try using extended desktop mode instead of mirror display mode. Mirror display also mirrors the display resolution. Extended desktop mode allows you to select the native resolution of the external display. From the Finder>Help menu> multiple displays with your Mac. Posted on Dec 29, 2019 10:49 AM. i9Q1Z.

mac not working with external monitor