Squeaky Doors

I just bought an 06' Silverado Ext. Cab.

Basically...I'm loving. However, I get a fair amount of squeaking from my driver's side doors. It just sounds like one of them isn't latching tight or something causing them to rub up on something. It seems to happen the most when I open and close the front door without opening and closing the back. Is this somewhat normal or is there something I can do to fix it? It's still under warranty, so if it's something that could be covered by that I'd like to know too.

Thanks.

I believe GM is Bumper to Bumper Warrenty for 36,000 miles or 3 years, so if you are within those terms then they will most likely replace whatever the problem is.. Let us know what the dealership says.