hmm..it probably could be related. have you thought about replacing the dc-in board? i had that problem (sister tripped on the cord while plugged in). at first, it would still charge. but then i had to have it plugged in a certain way. and then it wouldn't charge at all, and i couldn't use it. i bought a dc-in board on ebay cheap, and looked up some directions to replace it on ifixit.com, it actually wasn't as hard as i thought it would be.
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