So my son's 4s will not shut down, unless the power cord is plugged in. It started out the sound would not work and it would not shut off. I cleaned the connection area where the 30pin connector goes and got the volume/sound working, but it still will not shut off. If I hold the power button then slide to turn off...it will turn off and immediately turn back on with no input from me. I did a hard reset and I get the same thing. If I do the above process the sound stops working again until I plug and unplug the power cord. I figure it needs some more cleaning, but I'm not sure what other tools I should use besides cotton swabs, they don't fit well.