Pulse Audio 4 released

There is one particular feature why you might want to upgrade.

“Better handling of low latency requests
Optimisations while mixing (generic, ARM NEON)
Default resampler is now speex-float-1 (lower CPU usage)
Major Bluetooth refactoring for better reliability and easier maintenance
Fixes for graceful hand-off to/from JACK
New module to apply ducking based on stream roles
Echo canceller infrastructure fixes
Bash and zsh completion for command line tools
Solaris and OS X fixes
Lots of other enhancements, bug fixes, and documenation and i18n updates”

http://www.freedesktop.org/wiki/Software/PulseAudio/Notes/4.0/