This is still an issue in Lucid official release.
Reassigning it to the MythTV devs, while the correct course of action, resulted in a political dispute and no resolution for users:
http://<email address hidden>/msg06978.html
According to a later comment on the thread (dated May 2010), there is another version of MythTV on the way with better pulseaudio support:
http://<email address hidden>/msg06979.html
....still no word on that.
In the meantime, the following workaround restored functionality on my system, allowing me to use Mythfrontend with the PulseAudio:default audio codec, and still get sound from other applications spawned while mythfrontend was running (i.e. VLC, Mplayer).
Here are my settings for mythfrontend (Utilities/Setup --> Setup --> General)
- Audio output device = "PulseAudio:default"
- Internal Volume Controls = on
- Mixer device = software
- Mixer controls = Master
- Master mixer volume = 50
- PCM mixer volume = 70
........I control the volume with the pulseaudio command line tool "pacmd" using LIRC and irexec, as shown in this script: