2nd Monitor Colour Issues

-I am using an NEC Spectraview Reference 271 with a 3.4Ghz i7 iMac as a 2nd monitor. (16gb Ram / AMD Radeon HD 6970M 2048 MB /OS X 10.8.5)
-Both monitors are calibrated and have their own unique icc profiles.
-When viewing the same website on Safari on both monitors, the colour is identical, but if I open a 2nd tab in Safari on the NEC the colour profile seems to go out the window and everything takes on a reddish hue…however, a quick check under system preferences confirms that both monitors are still on the correct calibrated icc profile.
-I have downloaded Firefox and the same thing happens.
-When I use Adobe Lightroom or Photoshop there are no issues in colour between the two monitors, this is purely web based.
-I have a MacBook Pro and if I connect the NEC to the MBP it does NOT exhibit this issue.

The strange thing is I have had the same set-up for a few months and this seems to have only started this week as I regularly have several tabs open in Safari on both monitors and bounce between projects. I have not downloaded any updates or changed anything in the set-up.

Any ideas?

Have tried to duplicate your problem with my iMac. I have an older Gateway monitor connected to my iMac . Both of which are calibrated. Sorry to say I get identical results on both monitors with multiple tabs open. No sign of a red bias. Now OK I am on Mavericks which is supposed to have better second monitor support. But I've used this system way back to Snowy with no problems.

Bit of a shot in the dark, but have you tried disabling flash to see if this makes any difference

Hi Chappers

Many thanks for your response...appreciated!!!

To this day, I still do not know what was causing the issue but a complete re-install of OS X sorted it out...I hear that Safari 6.1 can sometimes cause issues and as my MBP was not exhibiting the issue when the NEC was plugged into that I realised that it had to be OS based. Safari 6.0.5 seems to work fine and the colour issue is no longer prevalent...

Many thanks again!!!
JTN