I purchased a VL 546 which already had a charge on it. I have put music on it and now after not really using it except while loading to it and checking that the songs work, it won't turn on so I am assuming the battery is dead. I have tried charging it with the wall charger which came with it both while the player is in "on" mode and "off" mode and it still won't turn on. If I plug it into a usb port on the computer, the computer does not recognise that it is there (perhaps because battery is dead?) Should I have it in "off " mode or "on" mode to charge through the USB? OF course the manual does'nt say which way... any help would be great. Thanks!