- Once loaded, Press these buttons in this sequential order:

  FUNC -> MENU -> [down arrow] -> EXECUTE -> MENU -> 0 -> DEC/NO

- Video monitor now shows "Hacker Mode"

- Press UTILITY, then press MENU to load the new utility
  menu from disk.

- Click on or cursor over to "THE TEST" and hit enter.

- Now you have all the test mode stuff.

Supposedly in the HACKER mode, the S550 will support standard dump
format (SDX) sound files.