I have the same exact problem in 12.10 running the latest updates
Im crashing to the login screen without any errors to the Xorg.log ....... whenever i try to play a video .
What i did is uninstall my nvidia 310 drivers ( that was working perfectly , i only got this problem today though i was using 310 for almost a month) and used the open source ubuntu default nouveau and the problem is still here .
So there is nothing to do with the nvidia proprietary drivers. The culprit is somthing else and it isnt fixed yet although the bug says fixed.
I have the same exact problem in 12.10 running the latest updates
Im crashing to the login screen without any errors to the Xorg.log ....... whenever i try to play a video .
What i did is uninstall my nvidia 310 drivers ( that was working perfectly , i only got this problem today though i was using 310 for almost a month) and used the open source ubuntu default nouveau and the problem is still here .
So there is nothing to do with the nvidia proprietary drivers. The culprit is somthing else and it isnt fixed yet although the bug says fixed.