When I was assembling my new gaming station, I was struggling to get PA running. The error message was something like "ERROR Unexpected failure to initialize Coherent UI subsystem", and that was the end of it. first I thought it was a driver issue, since there were reported issues with the AMD catalyst and FOSS drivers, but as it turned out, setting the localization to "C" (non specified) does not sit well with the Coherent stuff... dpkg-reconfigure locales and setting some system wide locale like en_US.utf-8 made it start up.
