ML BUG? help?

I have been testing 10.8.4 on different machines and have had some odd things come up. Weird screen tearing and gui rendering issues for one... but the interesting one is that ML videos arent played back at their correct speed if they are just freerun in catalyst. Its really quite off.... Its almost like its not even steady at one speed. I have been able to duplicate this on several machines. Simple changing the OS back to SL resolves issues.. all other things are equal... quadruple checked... Not dropping frames, plenty of resources, does it with just one file of any res...not a machine performance issue. this has caused quite some headache... is there a fix for this I dont know about?.. I am about to start a tour and would like to be able to run ML so I can use 680 vid card? Please help

Hi! I have the same problems after upgrading to ML (Quadro 4000)... After reboting from the backup HDD (with installed SL) the same project runs perfect... Have you installed nVidia Web drivers for Mac on ML?

HI.. I have not installed any additional drivers as I have the mac edition gtx680 and supposedly dont need any in mac os? I responded in your other thread as well. If I am missing something I wish someone would fill me in... But this just isnt working well at all. I need Smooth tear free video... not getting it. Same files etc in SL with even an AMD card, and certainly quadro are far superior in playback quality. If there is a fix I need to know now! Sad as they seemed to have also fixed the poor performance with amd cards in ML but same tearing issues etc.

Note... I do wonder if this issue is only with catalyst? Movies play fine in other apps,, granted this can be taken with a grain of salt. I would love it if Richard could chime in here?