I've been in discussions with Adobe on my problem with this and their replies ( from engineers ) has been that there is a problem with the Blackmagic Intensity Pro driver 9.7 and Premiere CS6. A 9.7.1 version should fix it due March 8ish.
Having said that, I was experiencing playback freezes on the earlier 9.6 series driver so I'm not holding my breath.
Everything else works superbly though and I'm very happy with the CS6 package.
Grant.