I was listening to some music with Amarok this morning when I wanted to watch the new The Happening trailer. To my annoyance there was no audio! After conducting a bit of googling research, I learnt that it was because of Ubuntu using PulseAudio as its audio backend for Hardy. The fix is simple; install libflashsupport:
sudo apt-get install libflashsupport
Then maybe log out and log back in 
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It seems the reason libflashsupport isn't installed by default is because of some problems some people are having with it.
