Hi Ricardo,
With working HDMI output on the original panda board, and Wei's new release of patches to alsa-lib and pulseaudio, I've updated both alsa-lib and pulseaudio for 11.12 in ppa:linaro-maintainers/overlay. Sound on the panda over HDMI from my testing works out of the box. It's not perfect but it works. I will repeat this same test with my imx53 shortly.
For all on the dev list, be aware that audio is in a state of flux and while we'd like to avoid defects they are likely. The Multimedia WG is putting substantial effort into having a "just works" level of quality for supported boards.
A very bit thank you is in order for Wei Feng for his hard work on 11.12! Good job! One small sound for an ARM board, but a big noise for Linaro when we can say, "It just works."