I've have the flicker problem too. The first time, I forgot to plug in the system when I got to work. The "you are on battery now" balloon pops up, the system behaves as if the power adapter were unplugged (thus the flash as the monitor goes to low power mode).
The thing I noticed was the power adapter got VERY warm (ok, hot) when it was in this mode. The system seemed to be unable to charge the battery and run the system. I shut the system down and left it plugged in for a couple of hours, the charge came back and everything was fine again....until last night, when I forgot to take the power adapter home and I ran down the battery at home. This morning, it was back in the flicker mode, seemingly stuck at 7% battery.
The theory of the guy I work with (who has a EE background) is that the adapter doesn't have enough amps...
So, I shut my system down and was waiting for the battery to charge when the DHL guy arrived with my new EZ Dock!!! Cool!.
Guess what? The dock comes with a bigger adapter. It comes with a Liteon 7.1 amp adapter, and the default adapter is a 3.42 Amp Delta.
So... I plugged in the dock, powered everything on, booted the system. It's been running for 15 minutes now with no flicker. and the battery is at 14% now.
The plug on the Liteon looks similar to the Delta, but is a little shorter. I wouldn't plug it into the laptop directly without calling Acer first.
so, my experience at least would tend to indicate an underpowered default power adapater.