When cubase is exporting an audio mixdown (non-real time export) how come if I play a video file using quicktime the audio sounds choppy? Shouldn’t a quality i7 CPU be able to multitask? I’m curious what the nerd answer for this is, like if the audio driver is being utilized and causing the break in the audio stream.
Best to let the computer get on with the mixdown, just leave it alone, a good time for a few minutes of peace 
Sage words indeed. I personally leave my DAW well alone while the export is happening. I don’t even wiggle the mouse… My experience is that it’s not entirely a background non-realtime process and some things (like using the audio drivers, stressing the CPU, using the CD/DVD or plugging in USB sticks) seem to cause problems in the exported audio.
Mike.
Try doing a realtime export…
If you were to play the project back and check out your video, is it still choppy?
try recording your mix back to an audio track (Route the input of a new track to your stereo output, or send all your tracks to a group and set the group as the input on that stereo track.)
I totally agree Split and GargoyleStudio on this one
Clint