Okay so I've got a pretty bad problem lately. My Mac charger sometimes fails to charge my laptop, so it'll run on battery power a short while before it realizes the computer needs to be charged. It's never been much of a problem before, because as long as the computer is on, it'll detect it almost instantly. However recently the charger would just quit charging on me halfway while I'm playing a game. It's happened at least 4 times in the last month. I'd be using it for a few hours, play a few games, then all of a sudden my laptop shuts down due to lack of power. It takes about a few minutes before it's able to detect the charger again before it powers back on, and then I resume playing my games for another hour or two. Anyone experienced this before? I'm planning to bring it down to the service centre as it's almost out of warranty, but the problem is that it's a bit hard to duplicate this problem.