It sounds like there's a little clipping going on somewhere during your louder vocal parts.
Other than that, I really like the sound you've created here. It reminds me of an old radio, or sound pushed through a telephone. I imagine an old-fashioned detective sitting in a chair, listening to the radio. He sighs as the music plays, and takes a swig of something strong and alcoholic. He sighs again, gets up, and walks outside. The music fades from the telephone-esq sound to something more natural, as he walks down the street to the detective agency.
Now, If only I could animate...