Since this is the command in Universal Prefs. to toggle back and forth for all apps system wide.. try turning it on and off and see if it affects iTunes.

Holding down CNTL OPT CMD and clicking 8 will toggle between "black on white" and "white on black".

"If it turns out that President Barack Obama can make a deal with the most intransigent, hard-line, unreasonable, totalitarian mullahs in the world but not with Republicans? Maybe he’s not the problem."