Someone with access to IE7 would have to answer this (I don’t have it so I’m unable to check).
Check out the Optimal demo and see if the same thing occurs….you can also try another site that uses the Genesis Responsive Slider and see if the problem is the same. If it is, then it’s probably an issue with that particular plugin. If so, it would be best to contact the plugin developers over at SP Community forum to see if they are aware of the issue.
If someone with IE7 can take a look at this for us, that would be greatly appreciated 🙂