iPod touch 4th Gen. on iOS 5.1.1 not charging

[sirius_gamer]

Hey guys im new to this forum so if this thread is posted in a wrong section then kindly inform me. Im having a problem with my iPod touch. It is not connecting to iTunes, neither it is charging :/ At first I thought that there's some problem with my USB cable. But when I connected it to the device and then turned the device off, after some time I saw that the battery was charged. So to sum up, the problem is this, that the device only charges when I turn it off. Kindly help me please. Thanks!