[gentoo-user] macbook air external monitor causes black screen

[gentoo-user] macbook air external monitor causes black screen

[William Kenworthy]

Here is a wierd one,

I am using macbook air (mid 2012 - 5,2) and its working acceptably
finally (still some things to tune), with only one serious problem.

If I attach an external monitor/beamer/projector it works as expected,
after which I disconnect the cable (one of those display port adaptors),
set the resolution back to auto using the LXDE menu and suspend to
ram ... back at the office I resume the machine and start using it.  If
I leave it, it then blanks the screen and nothing Ive tried so far will
reactivate it (backlight off) except pressing the power button ...
whereupon the screen flicks on, and the machine shuts down - useful!  I
have not seen it actually blanking so cant see if its screensaver
related or not.  Its only after I attach/detach an external monitor that
this occurs - otherwise no problem.

Its a reasonably fresh amd64 install (copied from a dell server I have,
and reconfigured), LXDE desktop and xscreensaver, no xinerama, xorg.conf
only contains settings for mtouch.

Has anyone hints as to where to look?

BillK