Debian :: Flashplugin-nonfree Terrible Performance / No Spike In CPU

II installed flashplayer by every different method I can so far, and all of them have the same problem. This problem presents itself, for example, while playing a video on ...... As the video loads, flashplayer is fine, but as soon as it starts playing, the browser tab begins to run at roughly 1 frame per 10 seconds. When I turn the browser priority to maximum in System Monitor, it improves slightly, going to about 1 frame per second. The strange part is, my CPU and memory usage barely spike at all, to less than 30%. This happens regardless of browser (have tried iceweisel and chrome). It happens with hardware acceleration on, and off. I have tried installing flashplayer from the tar.gz on the adobe website, from the repository (all three packages), and manually placing the plugin in the browser myself. The issue presents itself the same every time.

My system specs are: 1.83GHz duel core intel centrino processor, 3GB RAM, ATI Mobility Radeon HD 2600. Nothing fancy, but flash player performs as flawlessly as flashplayer can under windows (and also performed well in my previous Ubuntu 10.04LL install).