Engine Flutter Noise... Please Help!

I purchased a 2004 Yukon two weeks ago. The engine has a constant flutter noise when I drive at all speeds. I took it into GMC service and they said that there is nothing wrong with the engine, but they do hear the noise. They told me that there is nothing that they can do to fix it, but they made a report to GMC and GMC could come out with a fix for it hopefully in sixth months. Other yukons have reported this as well.

My question is:

Does anyone have suggestions of what to do here?

Anyone have success fixing this?

Can I camplain to the dealer?

Thank you if you can add any help!