audacious has alot of debug code paths usefull in tracking down bugs. A use flag to enable them would greatly assist in resolving problems. audacious-plugins as well has a good number of them.
In particular the bread crumbs in audacious-plugins src/alsa/audio.c would be usefull in resolving #160397.
Time permitting I will attach a patch myself.
The 1.3 release (on which ebuild development is happening, 1.2.2 core & 1.2.5 plugins are frozen except for security bugs or something similarly earth-shattering) does not have any responders for 'debug' in configure.ac; as such I don't see a clean way to implement a USE-flag for this.
If you feel that this is incorrect and have a patch that bolts on a working USE-flag for debugging, you may reopen this bug.