Comment 10 for bug 353691

64bit plugin works great (incomparably better than the 32bit version with the wrapper) and I also found a workaround:
- uninstall pulse
- create /etc/asound.conf with this content:
ctl.mixer0 {
    type hw
    card 0
}

pcm.dsp0 {
    type plug
    slave.pcm "dmix"
}

- unmute and raise volume on the right channel on the mixer

Now everything works fine, as before (in Hardy and Intrepid).

While current release of 64bit flash is not perfect yet (The only major problem I saw is that facebook games are not working) it is much better in speed and stability in respect to the 32bit version+wrapper so I strongly recommend to use it (simply download it and unpack in /usr/lib/xulrunner-addons/plugins/).