Vote for the quality of recordings
Many recordings I've search for the language I'm studying end up being bad quality of either tape or speaking (and I don't mean speaking fast, I was listening to some recordings in my native language too, and sometimes I could barely catch what they were saying!), which is very frustrating trying to find one I'd be satisfied with. If people would be able to vote on the quality/clarity of other's recordings, maybe there would be less people just mumbling through the text while earning credits for a bad recording. Or a catch of earning an extra credit, if your recording is voted as good quality.
