Please try the following:
iPod® and iPhone® troubleshooting
Applies to:
- If your device is in a case or protective sleeve, remove it and then reseat it on the connector. If it is not seated correctly on the connector, it may prevent charging
- Try resetting your device. Depending on your model, you should refer to Apple support to perform this task
- Reset your SoundDock system. Turn the system off and unplug it from power for 60 seconds. Once you have reconnected the system to power, see if the device will charge