There seems to be all kind of weird libsdl-mixer packages in Extras, libsdl-mixer1.2.8 and libsdl-mixer1.2+ogg variant. Weird thing about these is how did they get to Extras as I can't see any package depending on them and that they cannot be installed with Application Manager in the first place.

libsdl-mixer1.2+ogg variant should be removed from extras-devel because it's used for building instead of the official package.