If is drivers, system->administration->hardware should launch 'jocket-gtk' which allows you to install the nVidia (and other) drivers from a GUI. At least it should, its been buggy the last release or two.
*edit- assuming that your Mini 311 is an nVidia ion model. if its got an intel video, you wont be able to install video drivers from jockey.
Its possible that you dont have the drivers, and that wont be helping. The real problem could be that adobe doesnt support hardware video decoding for flash with linux, its supported with windows. Blame adobe for that, not ubuntu, or linux.
Last edited by cascade9; 08-19-2011 at 10:34 AM.