Hi
I have exactly this problem.
I reported it to support a month ago but nothing has changed.
Here is the old banner
https://screencast.com/t/F2xwbjmJNn4M
Unfortunately the new one is not showing now but here is what it should look like
https://screencast.com/t/FKuTTEoqtY
I do not see any pattern to when it appears.
Each time it appears I think - oh good they have fixed it at last - and then it goes again.
I am using FF or Chrome or IE9 on a windows system -
but I have also checked it on a mac and the problem is the same.
If it is servers not updating then there is a serious problem around this.
Over a month and the banner keeps flip flopping randomly between the new and old ones -
this happens both in the banner upload page and in the shopfront.
Please Shapeways - you have some serious problems with your image management systems -
The forum is full of it. - its embarrassingly unprofessional for you and extremely annoying for many of us -
Hire someone who knows enough to fix it !