ok.. i figured it outish. We arent certain which step did it, so ill give you the jist of all of them. first make sure these packages are installed:
pulseaudio libao4 paprefs libpulse-mainloop-glib0 pulseaudio-module-jack pavucontrol pulseaudio-module-hal pulseaudio-module-x11 gstreamer0.10-pulseaudio pulseaudio-utils libasound2-plugins paman pulseaudio-module-gconf libgconfmm-2.6-1c2 libpulse-browse0 pavumeter libglademm-2.4-1c2a pulseaudio-esound-compat libpulse0 libpulse-dev pulseaudio-module-bluetooth pulseaudio-module-zeroconf
we then uninstalled whatever the default flash player was, and installed the "official" one, which was the adobe-flash-installer.
once this was done, create a file called /etc/asound.conf and paste this into it:
after this, delete the ~/.pulse folder, it will be recreated.
then sound worked in firefox. now then, im not certain which steps are not needed and being as this computer is 80 miles away from me, it is difficult for me to poke further, however, ill watch this thread and if this doesnt work, let me know and ill gain access again and we can look further. good luck!
before trying sound in firefox/flash, killall -9 pulseaudio it will restart.