iphone Ear piece broken (no sound)

Hello,

Okay, yesterday I unplugged my headphones and then decided to call someone. But suddenly no sound came out of the ear piece of the phone, and it wasn't reception problems.

I called my home phone to test and my home phone was ringing but no sound was coming out of the iPhone 4, but if I put it on speaker, it comes out, and if I use my headphone, sound comes out of the headphones too.

I've had my iPhone since launch date in Australia, so is this mostly a hardware problems? Maybe some wire broken?

Thanks.

I've had it since mid july.

Yeah, that's what I'm planning to do tomorrow. I checked the genius appointment availability in Sydney and there isn't any until Tuesday, which is when I'm going overseas too for holiday...
So I guess I'm just going to rush in and hope some genius will serve me without booking...