Humotropy

If you are having problems hearing sound in youtube videos using Firefox 3.0 Beta 5 on Hardy Heron, even when regular movies (maybe played through Totem) sound fine, the problem is caused when flash players try to change the system audio settings.  To fix this, you need to install the libflashsupport package:

sudo apt-get install libflashsupport

That should do it.  Enjoy.