slideshow in responsive mode

Hi,
I have a question about the slider on the homepage does not work well with center alignment of the call to action button, just floating resolution.
Then see a mobile phone and the call to action button is not aligned in the center but it is in the texts on the left, but after loading all slider, the second repetition of the loop aligns well in the center.
See problem on site http://www.vola.it
You know how to give an explanation for this strange behavior?
Thank’s
Alessandra

Ticket