No sound AT All from iPhone 4?

My iPhone's sound has just gone completely silent, no sounds through speakers, through headphones and when I plug in my earphones there's no static sound or any feedback of plugging it in. I have restarted it many times (because this has happened before and all I had to do was restart it and it was fixed) but it's still not working. Any suggestions?

Go to the apple store. The sooner the better, most iphones have a 1 year warrantee unless you purchased an extended warantee.