Will the apple store replace my iPhone 3G S?

So i just traded in my month old 3g for a new 3g S. There some problems with the new phone though. First the silencer switch is loose. Second it doesn't charge with the wall charger that came with it. Third the headphone jack doesn't work properly with any of my third party headphones or cette adapters. It also crackles when using the apple headphones that came in the box. There is one thing i am worried about though. Some how there is a small half inch scratch on the screen near the earpiece. No idea how this happened i have never dropped and have treated it like a baby. Just wondering if they will replace it because of its defects. The rest of the phone is absolutely pristine cosmetically. Thanks