My iMac's display is currently set to Screen Spanning Mode. I've been able to play videos in fullscreen on the external display using QuickTime, while I continue using the iMac's display for desktop work. However, I can't seem to do the same with VLC which insists that I use the iMac's display for fullscreen videos and not the external display. With VLC, I only get to view fullscreen videos on the external monitor when my system's display preference is set to Mirroring Mode. Does anyone know how can I use VLC to display fullscreen videos only on my external display and not on my iMac in Screen Spanning Mode? It's disappointing that QuickTime doesn't output in 5.1 surround while VLC can. I want to use VLC to watch videos on my external display in Screen Spanning Mode and I'd really appreciate any help.
I can't find a workaround to this, I guess this is a VLC limitation. I just use quicktime if I want to utilize my other monitor for screen spanning.
Have you tried changing the number of Video device under Interface > Main Interfaces > macosx? Maybe this will solve your problem.