A monitor attached through a Mac docking station can remain blank after wake because its automatic input selection interferes with detection timing. Plugable describes disabling that scan and manually choosing the connected HDMI, DisplayPort, or USB-C source through the monitor's own menu.

This check matters when a dock otherwise reconnects its peripherals correctly. Labels such as Auto Select and Input Auto Switch vary between monitor manufacturers, so consult the screen's controls. Establishing a fixed input helps separate the monitor's source-selection behavior from a genuine dock or macOS reconnection problem before more disruptive changes are attempted.