These unwanted sounds usually appear when the hinges get loose. Loose hinges cause vibrations while the music box is playing. To fix this problem fill in the gaps of hinges with superglue. This will fill the gaps and prevent vibrations.
Important: use a very small drop! After putting the glue in, keep opening & closing the lid to prevent it from complete hardening. Glue gel is recommended over liquid glue.
TIP: You can also try a thick greaser instead of glue.