As is the case with other Medarot games, Medarot 4 has a Test Mode screen that contains a sound test (with music and sound effects), as well as an option to erase your save. In this game, from the title screen, Select must be held down before holding Start (not A), and it must remain held down during the fadeout.
A few things unique to Medarot 4:
The Test Mode graphic (テストモード) has a unique 72×16 font, so it would probably be a good idea to create a custom graphic of the same size.
Each music track and sound effect are named (instead of just having ID numbers), so these will need to be translated.
As is the case with other Medarot games, Medarot 4 has a Test Mode screen that contains a sound test (with music and sound effects), as well as an option to erase your save. In this game, from the title screen, Select must be held down before holding Start (not A), and it must remain held down during the fadeout.
A few things unique to Medarot 4:
Medarot 4 Saves Test Mode Voices.zip