the new OS4 operating system on my iPhone 3G is not getting along well with my iPhone functions. My phone is slower, and with the latest update to allow for accurate signal strength indications, I am not able to text or receive texts. I want to restore my iPhone to factory settings to see if I get my text ability back, but I'm afraid of what will happen to the almost 2000 songs I have on it. Does anyone know? I don't want to risk them since I have hundreds of dollars invested.