I was having some problems with my website, I test on various platforms and eventually discovered that part of my site doesn’t work properly. Its a .png image that sits on the left of the page to blur the bottom of the menu into the background to balance the page. The gradient moves from the light grey of the menu to a darker grey. The only browser this worked on was Firefox on Windows.

After some head scratching, Florian suggested that it was that I had usesd the .png file format and a different colour profile for the image.

Switched to GIF.