Awkward T42 problem...

I registered specifically to make this thread.

This is a difficult problem to explain, so bare with me.

For the last month or so, my computer has had an issue. The port for the adapter (on the computer) seems to make a very high-pitched noise at times. While this noise occurs, my computer claims it's on battery power and is actually discharging the battery. But what confuses me further, is that when I remove the battery during this instance, the computer states it's running on AC power BUT the computer reacts as if it was on battery power (lags on games etc...).

Now this problem is inconsistent at times. One day it'll do it all day, and the next week it won't even do it. Sometimes I toggle the adapter plug till it works fine. But most recently, it's been terrible.

I've tried different adapters and different batteries. Problem seems to consist.