I'm running 2.34 of the firmware, and consistently get this message with DynDNS enabled. I've tried resetting the device via the UI, power cycling it, removing the DynDNS config info, rebooting, and re-entering it, all to no effect.
Is there a list of what the different error codes mean? For example, if I remove my domain name from the config it returns an error code of 2 instead of 12, so there's got to be some information somewhere on what they are.