I can reproduce this issue on a laptop, and the new version ca fix this issue.
my original env are: OS: Ubuntu 12.04 Kernel: linux-image-3.13.0-40-generic Package: xserver-xorg-video-intel-lts-trusty (2:2.99.910-0ubuntu1~precise1) and after I enabled precise-proposed repo and updated xserver-xorg- video-intel-lts-trusty to version 2:2.99.910-0ubuntu1.3~precise1, this issue was fixed. changed tag from verification-needed to verification-done ** Tags removed: verification-needed ** Tags added: verification-done -- You received this bug notification because you are a member of Ubuntu-X, which is subscribed to xserver-xorg-video-intel in Ubuntu. https://bugs.launchpad.net/bugs/1373776 Title: internal panel brightness set to 0 when switching back to internal- only mode To manage notifications about this bug go to: https://bugs.launchpad.net/hwe-next/+bug/1373776/+subscriptions _______________________________________________ Mailing list: https://launchpad.net/~ubuntu-x-swat Post to : ubuntu-x-swat@lists.launchpad.net Unsubscribe : https://launchpad.net/~ubuntu-x-swat More help : https://help.launchpad.net/ListHelp