[Ernst theodor amadeus Hoffmann]

From what I can tell, and I could be wrong, but it seems as if exporting to an external hard drive seems to solve the problem. At least, it did for me. The first time around I managed to make a HD render, no problem on the same hard drive i was running adobe premiere pro on: https://www.youtube.com/watch?v=MIsoFl2yduk&feature=youtu.be

However, after that, I got choppy renders. However, on a whim, I exported a few samples of video to which I have known to be choppy to the external, and voila! It worked for me. So, just a suggestion. In any instance, best wishes!