I have worked on 6 units of 2011 MacBook Pro that had this issues. Two of them were repaired out-of-warranty, which cost $210+tax for parts and $100 for labor.

I have worked on 6 units of 2011 MacBook Pro that had this issues. Two of them were repaired out-of-warranty, which cost $210+tax for parts and $100 for labor. I talked to AppleCare rep a few hours ago and Apple will refund me the repair cost.