Since the update to 12.04, there's been a problem specifically related to audio/video playback in Google Chrome.
The problem only affected the Google version but not the Chromium nor the Firefox Browsers.
Update July 19th 2012:
Here's what I did.
I'm no expert, but I think there are some problems related to the integrated version, so untill a new version is released, I'll stick to the "original" plugin.
Hope it works for you!
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