Here is the link with the video:
https://lne.box.com/s/dld39nb1vqilhksoby0btx2aqksqj8ob
(you can download for clearer image quality)

It starts around the :46 mark.  The only thing i can think of, it's by the electrical lines, but it's recording straight to the memory card, so kind of confused what's up.
I noticed when i was a little bit further away from the power lines the interference went away.   Is that would it could be?

Had my new Spark for about a month now and love it.   Still learning.

Please and Thanks.

-Eddie.

AH, you know what i think it was?.....
It was early in the morning and the sun was shining on the left, so that must have definitely been the shadow of the rotors going very fast!  

Has anyone else had that issue?

Yes shadows/reflections of the rotors, raise spark higher and turn camera slightly down, nice video.