Periodic Pixelation in FCPX

Within Final Cut X (latest update installed) and within my exported videos, I'm experiencing frequent pixelation on the screen. When playing at full speed, it just looks like there is some static on the screen but in the frame grab shown here, it's clearly pixelation.

This is not on my source files. Anyone else experiencing this and have a solution?

FYI, I am working on a Spring 2010 15" MacBook pro with the 2.6ghz i7 with 8gb of RAM. Final Cut sure is taxing to this machine - fan comes on instantly when I load the program and the program itself crashes at least once a session.

Thanks,

Jonathan

Assuming you didn't export proxy media, it sounds like you may need to do some maintenance within fcpx....i.e.trashing preferences, deleting render files, etc.
If you did edit with proxies, make sure you are changing your preferences back to optimized or original media before exporting.

Need more than 8GB RAM, and I'd like to know what graphics processor that 15" runs.