Note to self:
If you've been on 4 dozens on tutorials on how to get flash player working on Ubuntu, even though you have it already installed (flashplugin-nonfree), stop what you're doing and go to Synaptic and mark gnash for complete removal (if you have it installed somehow). Restart Firefox.
And then if it's still not working, continue your journey and I bid you good luck.
p/s: Logo hari merdeka this year looks like it's derived from Ubuntu's jek. Hmmmm....
UPDATE: huh! note to self again: if flash is playing but no sound in Hardy, sudo apt-get libflashsupport -> restart Firefox