I uninstalled the drivers and the Mac works much faster indeed. not just on FCP, where I can actually play clips but all around.

Thank you for the pointer.
I would have never considered uninstalling drivers and temporarily reinstalling when needed. I still think it is pathetic especially because it used to work perfectly, but given the issues I have had with 2 new Macbook Pros - it is an annoying detour but it works.

No issue whatsoever on my MacBook Pro, MacPro and Imac. All on 10.6.3 and the newest drivers. It works like a charm here...

An interesting fact was that even when the driver was installed and the beachball spun before playing, scrubbing a clip was never a problem, always worked immediately...

How do you uninstall the SXS drivers? Would like to test the theory.

Thanks

I used the uninstaller on the install disk image