So everything was working perfectly on my system. I have Debian SID, with the debian-multimedia repos and liquorix repos for kernels. Flash worked perfectly one boot, then the next boot the video still works perfectly but no audio. I found several "fixes" on the web, including creating .asoundrc in your home directory and another that said to
edit /etc/firefox/firefoxrc -- change the line FIREFOX_DSP="none" to FIREFOX_DSP="aoss"
neither of those have done anything. Have tried using both the flashplugin-nonfree and flashplayer-mozilla, same thing on either. ALL other sound works, smplayer, amarok, system sounds, etc.