I see this on older models so we install new batteries and maybe more. It's OK for the battery to charge slowly. It's a great way to extend its life span.
Bob
My Macbook pro powercord, when plugged in, causes interference with the trackpad and the headphone jack. The trackpad does not navigate smoothly and the headphones have severe static. Obviously there is an electrical interference issue but I am not sure the cause - whether it is the battery, hardware, or the powercord. My battery is very slow to charge, if that helps. Thank you.

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