GH13 GH17 light pulsing?

[The Bush Pig]

I have recently been filming a few things practicing, but when i film indoors with lights on(only when lights on) there is like a pulsing sort of effect? I have hacked gh1, with the native 24 ipowell blackout patch. filming on fhd, smooth mode, 1/60th shutter speed, same thing with 1/50th shutter as well. It's not my computer either, because it is noticeable on camera playback. Any ideas?

Here is footage of it (can see the effect start when lights turned on, around 6 seconds)
http://vimeo.com/25454949

 

[UncleBenji1977]

it's the fluorescent lights... The higher the shutter the worse it will be. When shooting in places with those lights, I would bump it back 1/30.