Some grey tones not showing

Hi folks,

Two months ago my display had some stripes in it and it was replaced. An other problem i then had

was that the grey scale isn't what it should be. For instance check your difference between the:

1.

and the

$('body').off('.data-api')

at this link: http://twitter.github.com/bootstrap/javascript.html

There should be a difference between it. It doesn't show on my iMac but it does on my Windows PC,

iPad, iPhone etc.

I've tried to recalibrate the color profile but it doesn't seem to help. Any suggestions?

iMac 27", OSX10.8.2, 3.4 i7