My iPhone has stopped charging. I think there is a problem with the dock. I have tried several cords. It feels more difficult to plug the cord in. I can plug the cord in but it doesn't seem to connect. However, if the phone is off, it will turn on again but it won't charge. Once, it did start charging, but that was the only time. I went online and it said to airblast or blow into the dock. I blew but didn't airblast and there was no difference. I tried to plug it into the computer but it did not connect though it did turn on. A dialogue popped up that said "Because a USB device was drawing too much power from your computer, one or more of your USB devices have been disabled. To prevent damaging your computer, the USB device drawing too much power has been disabled. Other devices may have also been disabled. When you disconnect the device drawing too much power, your other USB devices will be enabled again." It does seem that the battery is draining fast. Any ideas?