As noted in my Blackmagick Intensity review, we noticed some odd behavior with Quartz Composer introducing some very large latency from the Intensity Card. We some noted up to 45 frames of delay. It looks like this may very well be a bug with Quartz Composer, as Apple is now aware of the situation: From Apples QC developer email list:Re: Issue with Quartz Composer and Decklink Intensity 10 bit HD ingest ? Hopefully we’ll see a fix shortly.