2007WFP Color Banding Problem

My monitor is 2007FWP Rev A00. It was bought in Hong Kong 2 years ago. I found that my monitor have the color banding problem like other users in previous posts.

e.g.

http://www.dellcommunity.com/supportforums/board/message?board.id=dim_monitor&thread.id=54714&view=by_date_ascending&page=1

http://www.dellcommunity.com/supportforums/board/message?board.id=dim_monitor&message.id=73389&query.id=154280#M73389

Therefore, I stated the situation to the CS department in HK. But they said they did not received any document about this problem from Dell US. So my monitor is normal. They cannot arrange replacement for me. What can I do?

Thanks for reply!