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I checked HDMI connection and everything seems to be fine (new monitor, new cable).
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Monitor won't work or receive signal if I unplug MacBook from the charger (monitor has its own power supply).Įvery now and then, monitor will shut/disconnect for a short while and come back online. It works fine while the lid is open, but as soon as I close it, various issues occur. I hooked up my old 2012 retina MacBook Pro to an external 4k monitor via HDMI.
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