laptop loses hdmi connection with projector

I've seen, in a classroom at my school, that I can use the projector if I plug it directly, but if I go through an automated A-B switch, XFCE fails to detect. Cable plugged in on the other end, and I stuck it into my machine, and literally nothing happened - no signal to the projector, no panels popping up on my machine, and when I manually opened Display, only one monitor (the laptop's built-in screen) was available. In that case, the Display control panel opens automatically, along with a second panel to choose mirror displays, left or right etc.īut, last weekend, in a live-coding situation (where my screen is supposed to be projected), the video guy said it was a direct line from the projector, but I got nothing. It seems that it pretty much always works if the cable is plugged into the monitor first, and it's a direct cable to the computer. My 'Display' settings panel enables 'Configure new displays when connected.' ThinkPad E470c, Ubuntu Studio 16.04, XFCE 4.12. Quite often, XFCE fails to detect when an HDMI monitor or projector is plugged in.

Laptop loses hdmi connection with projector