Hello, Is anyone having issues with their headphone jack? On day one of my iPhone 4, I had a issue where my music would crackle if the headphone plug moved around at all while plugged in. Today, no sound comes out at all unless I apply frontward pressure to the headphone plug. As soon as I let go, the sound cuts out. I plugged the same ($70) Sony earbuds into an iPod Nano with no issues at all. Lastly, has anyone successfully gotten their iPhone 4 replaced at a Genius Bar yet? I have an appointment on Monday. I've also gotten a random "No Sim" error 3 times. A simple restart fixes that problem but it is still annoying nonetheless. Thanks.