DVD Regions

I have resisted setting the region on my IMac 27" as I wasn't sure what region I wanted to settle on. It is currently on region 1, so today I decided to run with region 4 (New Zealand) to play some DVDs for the grandKids. But the DVD just keep getting ejected. I finally got a dvd to bring up the window to change the region however it seems stuck on 2 in the drop down box and I cannot change the number. I have not altered the regions at all since I purchased the IMac, so I should have in theory 5/4 changes available, so what gives?

Is there a padlock in the corner that is "locked"? If so, click it. See:

Can't change the drive code? - MacRumors Forums

lifeisabeach said:

Is there a padlock in the corner that is "locked"? If so, click it. See:

Can't change the drive code? - MacRumors Forums

Click to expand...

Yes I saw the padlock and unlocked it, but no difference