The sound sample that comes with the gbdk is broken. This is a fixed version
Keys:
- Select: change current channel menu
- Start: play current Sound
- Start A: play a song
- Arrows: navigate throught options
- Arrows A: Increments/Decrements current value by 10
- Arrows B: Increments/Decrements current value by 100
- Arrows A B: set Min/Max value to current option
- Select A: Dump Registers