This is somewhat difficult to diagnose without seeing it. First download and run Coconut battery: http://www.coconut-flavour.com/coconutbattery/en it
This will give us the true story of the battery condition. My first guess is that the AC plug in is bent open to far and failing to make good contact. Check to see if it can be burnished in to tighten it. After we know if that is tight and making good contact, we'll see if you need a DC in port change or a power adapter change. Let me know what you find. You have no need of the baggage of a husband when you have us around. Why buy the cow.........