Yes, I too have interference from the battery. The original cable I received (without a ferrite coil) was worse, but even the replacement (with the ferrite coil) can cause interference.
In my case the interference was highly dependent on placement of the cable. When I was using the 720 on the pilot's yoke in my Cherokee, I had to drape the cable off the glareshield and keep it away from the radio antenna leads running behind the pilot's side trim and into the panel near the left edge of the glareshield. Often I would have to reposition the lead during flight when interference crept back in.
Now that I am primarily flying with my Nexus 7 on the pilot's side, and have the 720 on the copilot's yoke with the battery and its power lead running on the right side of the glareshield away from the radios and the antenna leads, I do not have a problem with interference.