So, I renamed .config/monitors.xml and this has sort of fixed it. I'll attach my old monitors.xml in case that helps anyone.
** Attachment added: "monitors file from $HOME/.config/monitors.xml" https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1011086/+attachment/3183069/+files/monitors.xml.old -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1011086 Title: X freezes after connecting external monitor To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/xorg/+bug/1011086/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs