[SOLVED?] I rebooted and it's working. So idk what broke or fixed it.
I have alsa, pulseaudio and alsa-oss installed. The sound cards are Xtreme Audio PCI & onboard HDA Intel. I prefer Intel since it uses 5.1 surround, & b/c the Creative card has no open source driver.
I could watch Youtube videos w/sound, play ET and ETQW, etc. All of a sudden iceweasel won't play the audio from these flash videos.
One suggestion was to change /etc/iceweasel/iceweaselrc from ICEWEASEL_DSP="padsp" to ICEWEASEL_DSP="aoss". It worked for others, but not this box.
Sorry, idk what info is needed to resolve this issue. All help's greatly appreciated. TIA