BenQ Monitor will in a sense freeze

Recently my BenQ monitor will in a sense freeze. Basically when I am switching it from D-SUB to HDMI or HDMI to D-SUB nothing happens. The screen just sits at black. Then when I try to pull up the settings menu nothing comes up. So then I try to turn it off but the power button only works if I hold it down. Then when i turn it on it is working. It has done this twice now.

Someone suggested it could be the monitor adjusting the refresh rate when I switch from the xbox to the laptop and vice versa.