BeHappy is an AviSynth-based audio transcoding tool written in C#.
BeHappy is designed mostly for movie audiotrack transcoding. It's a powerful BeLight/BeSweet replacement with XML based plugin system for source, dsp and encoder plugins.
A rich selection of plugins is already integrated aswell most of the required encoder executables (except non redistributable encoders like most of the AAC encoders).
As prerequisite a working AviSynth environment is required to use BeHappy. If you have no knowledge about AviSynth, simply use the installer.
For further help and some screenshots have a look at the Wiki.