Description of problem: Sound/pulseaudio doesn't work while Firefox is running. How reproducible: Boot, log in. Sound works in totem, vlc, etc. Run Firefox and view some Flash video. Sound no longer works in any other application. Quit Firefox and sound now works in other applications. Steps to Reproduce: 1. start firefox 2. sound apps stop working 3. quite firefox 4. sound apps start working Expected Results: Other apps should be able to use the audio system while Firefox is running. Additional information: This is with NO desktop, just a simple window manager.
Do you have pulseaudio daemon running, and both alsa-plugin-pulseaudio and libflashsupport installed?
Your Flash plugin apparently bypasses PulseAudio. Install libflashsupport to fix that. AFAIR this is docuemnted in the release notes.