5d Mark III ISO/Quick Control Dial

[Canonkeen]

I've used Canon cameras for years.  I just recently purchased the 5D Mark III and love it.  I just noticed last night that when I press the shutter release half way and turn the quick control dial it is changing the ISO setting, not adjusting for exposure compensation.  Normal function would allow, after half pressing the shutter to turn the dial and get plus or minus exposure compensation.  When I do that now, it just changes the ISO.  It wasn't doing this before.  Is there a setting somewhere that I could have inadvertently changed that would cause this?  Any help would be appreciated. 

[Audionut]

Canon menu.

C.Fn2:Disp./Operation

Custom Controls

Quick Control Dial