Nightingale is a free, open source, multi-platform music player based on Songbird.
It works on Linux, BSD, Mac and Windows. Being Songbird based, almost all the Songbird plugins and adons are compatible.
To install Nightindale on Ubuntu 12.10 Quantal Quetzal and Ubuntu 12.04 Precise Pangolin, via PPA, do:
$ sudo add-apt-repository:ppa:trebelnik-stefina/nightingale
$ sudo apt-get update
$ sudo apt-get install nightingale