QLab 3.1.13 Release Notes
FIXED: A bug where the mouse could frantically flash and strobe when moving around the video surface editor.
FIXED: A bug that could cause QLab to freeze when connected to certain Blackmagic input devices.
FIXED: A race condition that could sometimes cause QLab to quit unexpectedly when stopping video cues.
FIXED: A bug where panicking both an audio/video/mic cue AND a fade cue that is fading out the audio/video/mic cue at the same time can sometimes cause the audio/video/mic cue to jump back to the starting (pre-fade) values at the start of the panic. (Yet another bug happened sometimes, but not always. But now, never! Let's raise a glass to race conditions! They sure do keep life interesting!)
ADDED: On launch QLab will now attempt to warn you if it detects that it may be running on non-Apple hardware.