Casio CZ/ VZ/ FZ - Pro Series

The DH series of controllers are actually officialy for VZ series
synths, as were the guitar controllers like the PG-380. The VZ-8M
has special settings for wind, guitar, or keyboard.
 I purchased a DH-200 cheap with the squeal problem. Easy fix as
they all seem to suffer from a capacitor that goes bad. Here is a 
link from the page I used to fix mine:
http://www.btinternet.com/~dorian.rose/
 Not a real easy project, but well worth the time. 
 
Good Luck,
Terry (The Casio Kid)