iPod Touch 4g battery won't charge

I was doing an upgrade to 5.1.1 via wifi and unplugged the device in mid-process by mistake. Now it will not boot nor charge.

In standalone it will not turn on at all. If plugged into the wall socket or USB it will show the battery charging icon but it does not charge. I can put it in DFU mode and get iTunes to recognise it to do a Restore but the process will not complete, ending on a 200x error usually.

It is in an endless loop. I saw somewhere a trick to put the USB plug partially into the socket to only allow the charge to pass and not data, which sometimes overcomes this problem but it won't work for me.