vslider image moving???

hi. i have the vslider plugin going on my homepage. it was working fine until a litte while ago, but i have tried reverting to an old backup and it doesn’t fix the problem.

my problem is that the images in the vslider slideshow appear at different vertical coordinates. one is correct, but the second one moves down the page. weird i know.

my url is: http://www.forcetwelve.net/test/

any help is much appreciated.