Sometimes when I plug my iPod touch into a dock or cable I get the message
Charging is not supported with this device. What's that mean? Did Apple change the pin configuration of the dock connector?
Is the charger one designed for an older iPod with charging on the firewire pins in the dock connector. The spec has changed in more recent devices to only charge from the usb power pins so it is detecting the older configuration and giving you this message
It could be that your charger does not match your device/iPod.
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