Why does Pangu keep timing out?

I've got a problem with the Pangu Jailbreak. It'll work fine up until just after the reboot. It says the reboot is successful and to unlock the device. I do, and then it says it's waiting for a response. It says this until the jailbreak times out. Why does this keep happening and how can I stop it? I have an iPad 2 16GB. Thanks for your time.