I have been having a problem with my ipod touch 4g lately. I had it for about over a year running ios 6.1.5. It drains quickly to 20% and it isn't accurate. But the real problem is when it dies at around 13% battery. It dies out(shuts off) but when I turn it back on, it reboots and turns back on. Then I use it for 2 minutes and it dies out again, but then it stills turns back on. It died around 5 times and it I turned it on 5 times. Anyone has any idea what is happening?