a99 - Pulsing / flickering in video mode? Didn't see this with A77...

I am noticing something that I didn't with the A77.

If I have steadyshot ON and walk around recording video, sometimes I get a "pulse" or "jump" in the video.  For both videos I've noticed this in I'm pretty sure I was using autofocus at the time, and I'm absolutely sure I was using IS ON in video mode.

Will throw something up on Youtube to show you what I'm talking about.  I don't know if it's just some bug with the IS + AF being on together or what.  I shot hours like this with the A77 and never saw it before.

Lenses used: 24-70 CZ and Sigma 70-200 OS.  The lens IS was off on the latter (it's too noisy for video).

Shawn