Audio was not working for Flash 9 in Firefox on Fedora 8, so after a lot of searching I discovered the following solution. In a terminal type: sudo /sbin/modprobe snd-pcm-oss

You may not need the /sbin/, but I did. Then restart your Firefox window(s). Audio should be working fine now.

Just confirming that the guide on this page works as described. I was able to install VMWare on Fedora 8, bypassing the problems with compiling certain parts of the program.