I'm using Litebox (same as Lightbox, but using moo.fx) in combination with sIFR. See here: http://www.brokinterieur.nl

After a search on Google I came across this topic: http://cssbeauty.com/skillshare/discussion/491/lightbox-20-and-some-werid-spacing-issue/#Item_0

The problem is that some overlay appears in Firefox - also when the Litebox isn't active. The sIRF text isn't visible and if you look close the text is slightly lighter. Referring to the topic above I think the problem is in my main cssfile, but I can't find it. On sites like www.retecool.com the sIRF text disappears automatically when the lightbox is active.