If you find one, please drop me a note. List of known bugs and malfunctions:

- Closing window when using Mwm (Motif) window manager seems to hang
  application, I cannot reproduce this with any other window manager. Mwm's
  f.kill command hang, but closing window with xkill does not. So, replacing
  f.kill with f.exec "xkill" in mwm's config works as a workaround.

- Some artifacts at the start of sound when using unsigned sample formats.