I just received an ASUS MeMO Pad 8 for Christmas. When I opened the box I immediately charged the tablet to 100% with the AC adapter. The tablet was turned off during this initial charge and charged to 100% with no problems. I used the tablet over the next 2 days and the battery went down to 38%. I turned the tablet off and began charging it with the AC adapter for approximately 6 hours. When I unplugged the tablet expecting a 100% charge the battery was still at only 38%! Without turning the tablet off I plugged the AC adapter in again and found that it was charging successfully in sleep mode and it eventually charged to 100% in sleep mode. My concern is why does the tablet not charge when it is turned off? Is this normal? If there is something wrong with the battery I want to return the tablet promptly for a replacement/repair. I would really appreciate any information you can provide me with on this issue!!