[Help Wordpress] Firefox rendering problem

I had the same problem. Mine was resolved adding third slide to slider. Weird?

Here is the setup:

autoHeight: true,
autoScaleSliderWidth: 570,
imageScaleMode: "none",
arrowsNavHideOnTouch: false,
fadeinLoadedSlide: false,
controlNavigationSpacing: 0,
controlNavigation: "bullets",
imageScaleMode: "none",
imageAlignCenter:false,
loop: false,
loopRewind: false,numImagesToPreload: 2,
keyboardNavEnabled: true,
arrowsNavHideOnTouch: true,
slidesSpacing: 1,
navigateByClick: false,

.

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